1656115221520 has 40 divisors (see below), whose sum is σ = 3896859085056. Its totient is φ = 654464807808.

The previous prime is 1656115221479. The next prime is 1656115221539. The reversal of 1656115221520 is 251225116561.

It is a tau number, because it is divible by the number of its divisors (40).

It is a super-2 number, since 2×1656115221520² (a number of 25 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1656115221520.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 124700832 + ... + 124714111.

Almost surely, 2^{1656115221520} is an apocalyptic number.

1656115221520 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1656115221520 is an abundant number, since it is smaller than the sum of its proper divisors (2240743863536).

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

1656115221520 is a wasteful number, since it uses less digits than its factorization.

1656115221520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 249415039 (or 249415033 counting only the distinct ones).

The product of its (nonzero) digits is 36000, while the sum is 37.

The spelling of 1656115221520 in words is "one trillion, six hundred fifty-six billion, one hundred fifteen million, two hundred twenty-one thousand, five hundred twenty".