61506601567921 has 2 divisors, whose sum is σ = 61506601567922. Its totient is φ = 61506601567920.

The previous prime is 61506601567913. The next prime is 61506601567969. The reversal of 61506601567921 is 12976510660516.

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., 57507045555600 + 3999556012321 = 7583340^2 + 1999889^2 .

It is a cyclic number.

It is not a de Polignac number, because 61506601567921 - 2³ = 61506601567913 is a prime.

It is not a weakly prime, because it can be changed into another prime (61506601561921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30753300783960 + 30753300783961.

It is an arithmetic number, because the mean of its divisors is an integer number (30753300783961).

Almost surely, 2^{61506601567921} is an apocalyptic number.

It is an amenable number.

61506601567921 is a deficient number, since it is larger than the sum of its proper divisors (1).

61506601567921 is an equidigital number, since it uses as much as digits as its factorization.

61506601567921 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4082400, while the sum is 55.

The spelling of 61506601567921 in words is "sixty-one trillion, five hundred six billion, six hundred one million, five hundred sixty-seven thousand, nine hundred twenty-one".