21507470353613 has 2 divisors, whose sum is σ = 21507470353614. Its totient is φ = 21507470353612.

The previous prime is 21507470353591. The next prime is 21507470353643. The reversal of 21507470353613 is 31635307470512.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14701565084644 + 6805905268969 = 3834262^2 + 2608813^2 .

It is a cyclic number.

It is not a de Polignac number, because 21507470353613 - 2²⁸ = 21507201918157 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21507470353643) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10753735176806 + 10753735176807.

It is an arithmetic number, because the mean of its divisors is an integer number (10753735176807).

Almost surely, 2^{21507470353613} is an apocalyptic number.

It is an amenable number.

21507470353613 is a deficient number, since it is larger than the sum of its proper divisors (1).

21507470353613 is an equidigital number, since it uses as much as digits as its factorization.

21507470353613 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1587600, while the sum is 47.

The spelling of 21507470353613 in words is "twenty-one trillion, five hundred seven billion, four hundred seventy million, three hundred fifty-three thousand, six hundred thirteen".