61655831 has 2 divisors, whose sum is σ = 61655832. Its totient is φ = 61655830.

The previous prime is 61655809. The next prime is 61655837. The reversal of 61655831 is 13855616.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-61655831 is a prime.

It is a super-2 number, since 2×61655831² = 7602882992601122, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 61655791 and 61655800.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61655837) by changing a digit.

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30827915 + 30827916.

It is an arithmetic number, because the mean of its divisors is an integer number (30827916).

Almost surely, 2^61655831 is an apocalyptic number.

61655831 is a deficient number, since it is larger than the sum of its proper divisors (1).

61655831 is an equidigital number, since it uses as much as digits as its factorization.

61655831 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 21600, while the sum is 35.

The square root of 61655831 is about 7852.1227066316. The cubic root of 61655831 is about 395.0554448688.

The spelling of 61655831 in words is "sixty-one million, six hundred fifty-five thousand, eight hundred thirty-one".