61331735720 has 32 divisors (see below), whose sum is σ = 146113842600. Its totient is φ = 23089594368.

The previous prime is 61331735701. The next prime is 61331735753. The reversal of 61331735720 is 2753713316.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 44184880804 + 17146854916 = 210202^2 + 130946^2 .

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, 45096185 + ... + 45097544.

Almost surely, 2^61331735720 is an apocalyptic number.

It is an amenable number.

61331735720 is an abundant number, since it is smaller than the sum of its proper divisors (84782106880).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

61331735720 is a wasteful number, since it uses less digits than its factorization.

61331735720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 90193757 (or 90193753 counting only the distinct ones).

The product of its (nonzero) digits is 79380, while the sum is 38.

The spelling of 61331735720 in words is "sixty-one billion, three hundred thirty-one million, seven hundred thirty-five thousand, seven hundred twenty".