155388909636 has 27 divisors (see below), whose sum is σ = 392794611391. Its totient is φ = 51795514824.

The previous prime is 155388909551. The next prime is 155388909653. The reversal of 155388909636 is 636909883551.

The square root of 155388909636 is 394194.

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

155388909636 is a `hidden beast` number, since 1 + 5 + 538 + 8 + 9 + 0 + 96 + 3 + 6 = 666.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 2332315 + ... + 2398013.

Almost surely, 2^155388909636 is an apocalyptic number.

155388909636 is the 394194-th square number.

It is an amenable number.

155388909636 is an abundant number, since it is smaller than the sum of its proper divisors (237405701755).

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

155388909636 is an frugal number, since it uses more digits than its factorization.

155388909636 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 131408 (or 65704 counting only the distinct ones).

The product of its (nonzero) digits is 41990400, while the sum is 63.

It can be divided in two parts, 155388 and 909636, that added together give a square (1065024 = 1032²).

The spelling of 155388909636 in words is "one hundred fifty-five billion, three hundred eighty-eight million, nine hundred nine thousand, six hundred thirty-six".