61365347521 has 2 divisors, whose sum is σ = 61365347522. Its totient is φ = 61365347520.

The previous prime is 61365347507. The next prime is 61365347567. The reversal of 61365347521 is 12574356316.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 59579439921 + 1785907600 = 244089^2 + 42260^2 .

It is a cyclic number.

It is not a de Polignac number, because 61365347521 - 2¹⁵ = 61365314753 is a prime.

It is not a weakly prime, because it can be changed into another prime (61365347821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30682673760 + 30682673761.

It is an arithmetic number, because the mean of its divisors is an integer number (30682673761).

Almost surely, 2^61365347521 is an apocalyptic number.

It is an amenable number.

61365347521 is a deficient number, since it is larger than the sum of its proper divisors (1).

61365347521 is an equidigital number, since it uses as much as digits as its factorization.

61365347521 is an evil number, because the sum of its binary digits is even.

The product of its digits is 453600, while the sum is 43.

The spelling of 61365347521 in words is "sixty-one billion, three hundred sixty-five million, three hundred forty-seven thousand, five hundred twenty-one".