21264165422740 has 12 divisors (see below), whose sum is σ = 44654747387796. Its totient is φ = 8505666169088.

The previous prime is 21264165422671. The next prime is 21264165422761. The reversal of 21264165422740 is 4722456146212.

It can be written as a sum of positive squares in 2 ways, for example, as 11938641994756 + 9325523427984 = 3455234^2 + 3053772^2 .

It is a super-2 number, since 2×21264165422740² (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 3 ways as a sum of consecutive naturals, for example, 531604135549 + ... + 531604135588.

It is an arithmetic number, because the mean of its divisors is an integer number (3721228948983).

Almost surely, 2^{21264165422740} is an apocalyptic number.

21264165422740 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21264165422740 is an abundant number, since it is smaller than the sum of its proper divisors (23390581965056).

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

21264165422740 is a wasteful number, since it uses less digits than its factorization.

21264165422740 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1063208271146 (or 1063208271144 counting only the distinct ones).

The product of its (nonzero) digits is 1290240, while the sum is 46.

The spelling of 21264165422740 in words is "twenty-one trillion, two hundred sixty-four billion, one hundred sixty-five million, four hundred twenty-two thousand, seven hundred forty".