21604145146520 has 32 divisors (see below), whose sum is σ = 49334838922800. Its totient is φ = 8512678086528.

The previous prime is 21604145146483. The next prime is 21604145146523. The reversal of 21604145146520 is 2564154140612.

It is a super-2 number, since 2×21604145146520² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21604145146523) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4030621415 + ... + 4030626774.

Almost surely, 2^{21604145146520} is an apocalyptic number.

21604145146520 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21604145146520 is an abundant number, since it is smaller than the sum of its proper divisors (27730693776280).

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

21604145146520 is a wasteful number, since it uses less digits than its factorization.

21604145146520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8061248267 (or 8061248263 counting only the distinct ones).

The product of its (nonzero) digits is 230400, while the sum is 41.

The spelling of 21604145146520 in words is "twenty-one trillion, six hundred four billion, one hundred forty-five million, one hundred forty-six thousand, five hundred twenty".