1938599640 has 192 divisors, whose sum is σ = 6683040000. Its totient is φ = 485989632.

The previous prime is 1938599623. The next prime is 1938599651. The reversal of 1938599640 is 469958391.

1938599640 is a `hidden beast` number, since 1 + 9 + 3 + 8 + 599 + 6 + 40 = 666.

It is a Smith number, since the sum of its digits (54) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 949741 + ... + 951779.

It is an arithmetic number, because the mean of its divisors is an integer number (34807500).

Almost surely, 2^1938599640 is an apocalyptic number.

1938599640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1938599640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3341520000).

1938599640 is an abundant number, since it is smaller than the sum of its proper divisors (4744440360).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1938599640 is a wasteful number, since it uses less digits than its factorization.

1938599640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2214 (or 2207 counting only the distinct ones).

The product of its (nonzero) digits is 2099520, while the sum is 54.

The square root of 1938599640 is about 44029.5314533325. The cubic root of 1938599640 is about 1246.8935428678.

It can be divided in two parts, 19385 and 99640, that added together give a square (119025 = 345²).

The spelling of 1938599640 in words is "one billion, nine hundred thirty-eight million, five hundred ninety-nine thousand, six hundred forty".