21010400664480 has 216 divisors, whose sum is σ = 76163612671692. Its totient is φ = 5273198493696.

The previous prime is 21010400664469. The next prime is 21010400664493. The reversal of 21010400664480 is 8446600401012.

It is a happy number.

21010400664480 is a `hidden beast` number, since 2 + 1 + 0 + 1 + 0 + 4 + 0 + 0 + 6 + 644 + 8 + 0 = 666.

It can be written as a sum of positive squares in 6 ways, for example, as 16289844900624 + 4720555763856 = 4036068^2 + 2172684^2 .

It is a super-3 number, since 3×21010400664480³ (a number of 41 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 24827017 + ... + 25659336.

Almost surely, 2^{21010400664480} is an apocalyptic number.

21010400664480 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21010400664480 is an abundant number, since it is smaller than the sum of its proper divisors (55153212007212).

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

21010400664480 is a wasteful number, since it uses less digits than its factorization.

21010400664480 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50486408 (or 50486380 counting only the distinct ones).

The product of its (nonzero) digits is 36864, while the sum is 36.

The spelling of 21010400664480 in words is "twenty-one trillion, ten billion, four hundred million, six hundred sixty-four thousand, four hundred eighty".