21375061504564 has 24 divisors (see below), whose sum is σ = 39606980652288. Its totient is φ = 10058789224320.

The previous prime is 21375061504481. The next prime is 21375061504579. The reversal of 21375061504564 is 46540516057312.

It is a super-2 number, since 2×21375061504564² (a number of 27 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 7 ways as a sum of consecutive naturals, for example, 10960267 + ... + 12762349.

It is an arithmetic number, because the mean of its divisors is an integer number (1650290860512).

Almost surely, 2^{21375061504564} is an apocalyptic number.

It is an amenable number.

21375061504564 is a deficient number, since it is larger than the sum of its proper divisors (18231919147724).

21375061504564 is a wasteful number, since it uses less digits than its factorization.

21375061504564 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1976535 (or 1976533 counting only the distinct ones).

The product of its (nonzero) digits is 3024000, while the sum is 49.

The spelling of 21375061504564 in words is "twenty-one trillion, three hundred seventy-five billion, sixty-one million, five hundred four thousand, five hundred sixty-four".