61665139 has 8 divisors (see below), whose sum is σ = 65843712. Its totient is φ = 57611400.

The previous prime is 61665113. The next prime is 61665167. The reversal of 61665139 is 93156616.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 61665139 - 2⁷ = 61665011 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 61665098 and 61665107.

It is not an unprimeable number, because it can be changed into a prime (61665179) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30187 + ... + 32164.

It is an arithmetic number, because the mean of its divisors is an integer number (8230464).

Almost surely, 2^61665139 is an apocalyptic number.

61665139 is a deficient number, since it is larger than the sum of its proper divisors (4178573).

61665139 is a wasteful number, since it uses less digits than its factorization.

61665139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 62417.

The product of its digits is 29160, while the sum is 37.

The square root of 61665139 is about 7852.7153902329. The cubic root of 61665139 is about 395.0753239892.

The spelling of 61665139 in words is "sixty-one million, six hundred sixty-five thousand, one hundred thirty-nine".