15801998436 has 243 divisors, whose sum is σ = 48287697003. Its totient is φ = 4344399360.

The previous prime is 15801998417. The next prime is 15801998447. The reversal of 15801998436 is 63489910851.

The square root of 15801998436 is 125706.

It is a perfect power (a square), and thus also a powerful number.

15801998436 is a `hidden beast` number, since 1 + 580 + 19 + 9 + 8 + 43 + 6 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 3582022500 + 12219975936 = 59850^2 + 110544^2 .

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 an unprimeable number.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 216465696 + ... + 216465768.

Almost surely, 2^15801998436 is an apocalyptic number.

15801998436 is the 125706-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 15801998436

15801998436 is an abundant number, since it is smaller than the sum of its proper divisors (32485698567).

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

15801998436 is a wasteful number, since it uses less digits than its factorization.

15801998436 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 252 (or 126 counting only the distinct ones).

The product of its (nonzero) digits is 1866240, while the sum is 54.

The spelling of 15801998436 in words is "fifteen billion, eight hundred one million, nine hundred ninety-eight thousand, four hundred thirty-six".