15399990 has 32 divisors (see below), whose sum is σ = 41067360. Its totient is φ = 4106592.

The previous prime is 15399983. The next prime is 15399997. The reversal of 15399990 is 9999351.

It is an interprime number because it is at equal distance from previous prime (15399983) and next prime (15399997).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15399997) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 28249 + ... + 28788.

It is an arithmetic number, because the mean of its divisors is an integer number (1283355).

Almost surely, 2^15399990 is an apocalyptic number.

15399990 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

15399990 is an abundant number, since it is smaller than the sum of its proper divisors (25667370).

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

15399990 is a wasteful number, since it uses less digits than its factorization.

15399990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57053 (or 57047 counting only the distinct ones).

The product of its (nonzero) digits is 98415, while the sum is 45.

The square root of 15399990 is about 3924.2820999515. The cubic root of 15399990 is about 248.7941396213.

The spelling of 15399990 in words is "fifteen million, three hundred ninety-nine thousand, nine hundred ninety".