21401664441504 has 48 divisors (see below), whose sum is σ = 56420482390272. Its totient is φ = 7103270594048.

The previous prime is 21401664441463. The next prime is 21401664441523. The reversal of 21401664441504 is 40514446610412.

It is a tau number, because it is divible by the number of its divisors (48).

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, 478376784 + ... + 478421519.

It is an arithmetic number, because the mean of its divisors is an integer number (1175426716464).

Almost surely, 2^{21401664441504} is an apocalyptic number.

21401664441504 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21401664441504 is an abundant number, since it is smaller than the sum of its proper divisors (35018817948768).

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

21401664441504 is a wasteful number, since it uses less digits than its factorization.

21401664441504 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 956798549 (or 956798541 counting only the distinct ones).

The product of its (nonzero) digits is 368640, while the sum is 42.

The spelling of 21401664441504 in words is "twenty-one trillion, four hundred one billion, six hundred sixty-four million, four hundred forty-one thousand, five hundred four".