61985709 has 32 divisors (see below), whose sum is σ = 95846400. Its totient is φ = 39547440.

The previous prime is 61985659. The next prime is 61985719. The reversal of 61985709 is 90758916.

It is not a de Polignac number, because 61985709 - 2⁸ = 61985453 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61985719) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 85852 + ... + 86570.

It is an arithmetic number, because the mean of its divisors is an integer number (2995200).

Almost surely, 2^61985709 is an apocalyptic number.

It is an amenable number.

61985709 is a deficient number, since it is larger than the sum of its proper divisors (33860691).

61985709 is a wasteful number, since it uses less digits than its factorization.

61985709 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 862 (or 856 counting only the distinct ones).

The product of its (nonzero) digits is 136080, while the sum is 45.

The square root of 61985709 is about 7873.1003423048. The cubic root of 61985709 is about 395.7587488307.

The spelling of 61985709 in words is "sixty-one million, nine hundred eighty-five thousand, seven hundred nine".