61660731 has 16 divisors (see below), whose sum is σ = 90955008. Its totient is φ = 36842400.

The previous prime is 61660657. The next prime is 61660777. The reversal of 61660731 is 13706616.

It is not a de Polignac number, because 61660731 - 2⁷ = 61660603 is a prime.

It is a super-2 number, since 2×61660731² = 7604091494908722, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (61660031) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10816 + ... + 15501.

It is an arithmetic number, because the mean of its divisors is an integer number (5684688).

Almost surely, 2^61660731 is an apocalyptic number.

61660731 is a deficient number, since it is larger than the sum of its proper divisors (29294277).

61660731 is a wasteful number, since it uses less digits than its factorization.

61660731 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26402.

The product of its (nonzero) digits is 4536, while the sum is 30.

The square root of 61660731 is about 7852.4347179712. The cubic root of 61660731 is about 395.0659100612.

The spelling of 61660731 in words is "sixty-one million, six hundred sixty thousand, seven hundred thirty-one".