21736403512457 has 8 divisors (see below), whose sum is σ = 23016396160296. Its totient is φ = 20456564273152.

The previous prime is 21736403512451. The next prime is 21736403512459. The reversal of 21736403512457 is 75421530463712.

It can be written as a sum of positive squares in 4 ways, for example, as 6954001057936 + 14782402454521 = 2637044^2 + 3844789^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21736403512457 - 2⁶ = 21736403512393 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21736403512451) 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, 38060348 + ... + 38627229.

It is an arithmetic number, because the mean of its divisors is an integer number (2877049520037).

Almost surely, 2^{21736403512457} is an apocalyptic number.

It is an amenable number.

21736403512457 is a deficient number, since it is larger than the sum of its proper divisors (1279992647839).

21736403512457 is a wasteful number, since it uses less digits than its factorization.

21736403512457 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 76704267.

The product of its (nonzero) digits is 4233600, while the sum is 50.

The spelling of 21736403512457 in words is "twenty-one trillion, seven hundred thirty-six billion, four hundred three million, five hundred twelve thousand, four hundred fifty-seven".