1864393440 has 192 divisors, whose sum is σ = 7228279296. Its totient is φ = 393357312.

The previous prime is 1864393423. The next prime is 1864393459. The reversal of 1864393440 is 443934681.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a junction number, because it is equal to n+sod(n) for n = 1864393392 and 1864393401.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 22339 + ... + 65021.

It is an arithmetic number, because the mean of its divisors is an integer number (37647288).

Almost surely, 2^1864393440 is an apocalyptic number.

1864393440 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 1864393440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3614139648).

1864393440 is an abundant number, since it is smaller than the sum of its proper divisors (5363885856).

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

1864393440 is a wasteful number, since it uses less digits than its factorization.

1864393440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42721 (or 42713 counting only the distinct ones).

The product of its (nonzero) digits is 248832, while the sum is 42.

The square root of 1864393440 is about 43178.6224884491. The cubic root of 1864393440 is about 1230.7764810951.

The spelling of 1864393440 in words is "one billion, eight hundred sixty-four million, three hundred ninety-three thousand, four hundred forty".