61566091 has 2 divisors, whose sum is σ = 61566092. Its totient is φ = 61566090.

The previous prime is 61566059. The next prime is 61566097. The reversal of 61566091 is 19066516.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 61566091 - 2⁵ = 61566059 is a prime.

It is a super-2 number, since 2×61566091² = 7580767122040562, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (61566097) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30783045 + 30783046.

It is an arithmetic number, because the mean of its divisors is an integer number (30783046).

Almost surely, 2^61566091 is an apocalyptic number.

61566091 is a deficient number, since it is larger than the sum of its proper divisors (1).

61566091 is an equidigital number, since it uses as much as digits as its factorization.

61566091 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 9720, while the sum is 34.

The square root of 61566091 is about 7846.4062474486. The cubic root of 61566091 is about 394.8636842020.

The spelling of 61566091 in words is "sixty-one million, five hundred sixty-six thousand, ninety-one".