51352516646021 has 2 divisors, whose sum is σ = 51352516646022. Its totient is φ = 51352516646020.

The previous prime is 51352516645993. The next prime is 51352516646099. The reversal of 51352516646021 is 12064661525315.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 47746524532996 + 3605992113025 = 6909886^2 + 1898945^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51352516646021 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51352516606021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25676258323010 + 25676258323011.

It is an arithmetic number, because the mean of its divisors is an integer number (25676258323011).

Almost surely, 2^{51352516646021} is an apocalyptic number.

It is an amenable number.

51352516646021 is a deficient number, since it is larger than the sum of its proper divisors (1).

51352516646021 is an equidigital number, since it uses as much as digits as its factorization.

51352516646021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1296000, while the sum is 47.

The spelling of 51352516646021 in words is "fifty-one trillion, three hundred fifty-two billion, five hundred sixteen million, six hundred forty-six thousand, twenty-one".