38399940 has 192 divisors, whose sum is σ = 130636800. Its totient is φ = 9326592.

The previous prime is 38399939. The next prime is 38399951. The reversal of 38399940 is 4999383.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 431416 + ... + 431504.

It is an arithmetic number, because the mean of its divisors is an integer number (680400).

Almost surely, 2^38399940 is an apocalyptic number.

38399940 is a gapful number since it is divisible by the number (30) 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 38399940, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (65318400).

38399940 is an abundant number, since it is smaller than the sum of its proper divisors (92236860).

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

38399940 is a wasteful number, since it uses less digits than its factorization.

38399940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 171 (or 163 counting only the distinct ones).

The product of its (nonzero) digits is 209952, while the sum is 45.

The square root of 38399940 is about 6196.7685127008. The cubic root of 38399940 is about 337.3728904055.

The spelling of 38399940 in words is "thirty-eight million, three hundred ninety-nine thousand, nine hundred forty".