61908857 has 2 divisors, whose sum is σ = 61908858. Its totient is φ = 61908856.

The previous prime is 61908853. The next prime is 61908919. The reversal of 61908857 is 75880916.

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., 58736896 + 3171961 = 7664^2 + 1781^2 .

It is a cyclic number.

It is not a de Polignac number, because 61908857 - 2² = 61908853 is a prime.

It is not a weakly prime, because it can be changed into another prime (61908851) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30954428 + 30954429.

It is an arithmetic number, because the mean of its divisors is an integer number (30954429).

Almost surely, 2^61908857 is an apocalyptic number.

It is an amenable number.

61908857 is a deficient number, since it is larger than the sum of its proper divisors (1).

61908857 is an equidigital number, since it uses as much as digits as its factorization.

61908857 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 120960, while the sum is 44.

The square root of 61908857 is about 7868.2181591514. The cubic root of 61908857 is about 395.5951227825.

The spelling of 61908857 in words is "sixty-one million, nine hundred eight thousand, eight hundred fifty-seven".