61558572100 has 81 divisors (see below), whose sum is σ = 136998338967. Its totient is φ = 24009108480.

The previous prime is 61558572079. The next prime is 61558572139. The reversal of 61558572100 is 127585516.

It is a happy number.

The square root of 61558572100 is 248110.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 17381258244 + 44177313856 = 131838^2 + 210184^2 .

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 106687012 + ... + 106687588.

Almost surely, 2^61558572100 is an apocalyptic number.

61558572100 is the 248110-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61558572100

61558572100 is an abundant number, since it is smaller than the sum of its proper divisors (75439766867).

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

61558572100 is an equidigital number, since it uses as much as digits as its factorization.

61558572100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1254 (or 627 counting only the distinct ones).

The product of its (nonzero) digits is 84000, while the sum is 40.

The spelling of 61558572100 in words is "sixty-one billion, five hundred fifty-eight million, five hundred seventy-two thousand, one hundred".