61865905 has 8 divisors (see below), whose sum is σ = 74548584. Its totient is φ = 49286400.

The previous prime is 61865897. The next prime is 61865939. The reversal of 61865905 is 50956816.

It can be written as a sum of positive squares in 4 ways, for example, as 21123216 + 40742689 = 4596^2 + 6383^2 .

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

It is not a de Polignac number, because 61865905 - 2³ = 61865897 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 24466 + ... + 26875.

It is an arithmetic number, because the mean of its divisors is an integer number (9318573).

Almost surely, 2^61865905 is an apocalyptic number.

It is an amenable number.

61865905 is a deficient number, since it is larger than the sum of its proper divisors (12682679).

61865905 is a wasteful number, since it uses less digits than its factorization.

61865905 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51587.

The product of its (nonzero) digits is 64800, while the sum is 40.

The square root of 61865905 is about 7865.4882238803. The cubic root of 61865905 is about 395.5036144287.

The spelling of 61865905 in words is "sixty-one million, eight hundred sixty-five thousand, nine hundred five".