165521254140 has 96 divisors (see below), whose sum is σ = 561769125120. Its totient is φ = 40126363200.

The previous prime is 165521254139. The next prime is 165521254153. The reversal of 165521254140 is 41452125561.

165521254140 is a `hidden beast` number, since 1 + 6 + 55 + 21 + 2 + 541 + 40 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 165521254095 and 165521254104.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 13926826 + ... + 13938705.

It is an arithmetic number, because the mean of its divisors is an integer number (5851761720).

Almost surely, 2^165521254140 is an apocalyptic number.

165521254140 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

165521254140 is an abundant number, since it is smaller than the sum of its proper divisors (396247870980).

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

165521254140 is a wasteful number, since it uses less digits than its factorization.

165521254140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27865560 (or 27865552 counting only the distinct ones).

The product of its (nonzero) digits is 48000, while the sum is 36.

The spelling of 165521254140 in words is "one hundred sixty-five billion, five hundred twenty-one million, two hundred fifty-four thousand, one hundred forty".