61650011561 has 2 divisors, whose sum is σ = 61650011562. Its totient is φ = 61650011560.

The previous prime is 61650011459. The next prime is 61650011567. The reversal of 61650011561 is 16511005616.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 58924649536 + 2725362025 = 242744^2 + 52205^2 .

It is a cyclic number.

It is not a de Polignac number, because 61650011561 - 2²² = 61645817257 is a prime.

It is not a weakly prime, because it can be changed into another prime (61650011567) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30825005780 + 30825005781.

It is an arithmetic number, because the mean of its divisors is an integer number (30825005781).

Almost surely, 2^61650011561 is an apocalyptic number.

It is an amenable number.

61650011561 is a deficient number, since it is larger than the sum of its proper divisors (1).

61650011561 is an equidigital number, since it uses as much as digits as its factorization.

61650011561 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5400, while the sum is 32.

The spelling of 61650011561 in words is "sixty-one billion, six hundred fifty million, eleven thousand, five hundred sixty-one".