165511394780 has 48 divisors (see below), whose sum is σ = 358116123456. Its totient is φ = 64208033280.

The previous prime is 165511394773. The next prime is 165511394791. The reversal of 165511394780 is 87493115561.

It is a super-2 number, since 2×165511394780² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 129449 + ... + 589728.

It is an arithmetic number, because the mean of its divisors is an integer number (7460752572).

Almost surely, 2^165511394780 is an apocalyptic number.

165511394780 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

165511394780 is an abundant number, since it is smaller than the sum of its proper divisors (192604728676).

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

165511394780 is a wasteful number, since it uses less digits than its factorization.

165511394780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 719534 (or 719532 counting only the distinct ones).

The product of its (nonzero) digits is 907200, while the sum is 50.

The spelling of 165511394780 in words is "one hundred sixty-five billion, five hundred eleven million, three hundred ninety-four thousand, seven hundred eighty".