165612564545220 has 384 divisors, whose sum is σ = 559234005120000. Its totient is φ = 40446384168960.

The previous prime is 165612564545137. The next prime is 165612564545231. The reversal of 165612564545220 is 22545465216561.

165612564545220 is a `hidden beast` number, since 1 + 6 + 5 + 6 + 1 + 2 + 5 + 64 + 54 + 522 + 0 = 666.

It is a super-3 number, since 3×165612564545220³ (a number of 44 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 921418521 + ... + 921598239.

It is an arithmetic number, because the mean of its divisors is an integer number (1456338555000).

Almost surely, 2^{165612564545220} is an apocalyptic number.

165612564545220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 165612564545220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (279617002560000).

165612564545220 is an abundant number, since it is smaller than the sum of its proper divisors (393621440574780).

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

165612564545220 is a wasteful number, since it uses less digits than its factorization.

165612564545220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 180780 (or 180772 counting only the distinct ones).

The product of its (nonzero) digits is 17280000, while the sum is 54.

The spelling of 165612564545220 in words is "one hundred sixty-five trillion, six hundred twelve billion, five hundred sixty-four million, five hundred forty-five thousand, two hundred twenty".