61556980 has 12 divisors (see below), whose sum is σ = 129269700. Its totient is φ = 24622784.

The previous prime is 61556959. The next prime is 61557007. The reversal of 61556980 is 8965516.

It can be written as a sum of positive squares in 2 ways, for example, as 34245904 + 27311076 = 5852^2 + 5226^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1538905 + ... + 1538944.

It is an arithmetic number, because the mean of its divisors is an integer number (10772475).

Almost surely, 2^61556980 is an apocalyptic number.

It is an amenable number.

61556980 is an abundant number, since it is smaller than the sum of its proper divisors (67712720).

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

61556980 is a wasteful number, since it uses less digits than its factorization.

61556980 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3077858 (or 3077856 counting only the distinct ones).

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

The square root of 61556980 is about 7845.8256417027. The cubic root of 61556980 is about 394.8442049700.

The spelling of 61556980 in words is "sixty-one million, five hundred fifty-six thousand, nine hundred eighty".