61553780 has 12 divisors (see below), whose sum is σ = 129262980. Its totient is φ = 24621504.

The previous prime is 61553777. The next prime is 61553797. The reversal of 61553780 is 8735516.

It can be written as a sum of positive squares in 2 ways, for example, as 37797904 + 23755876 = 6148^2 + 4874^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 61553780.

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, 1538825 + ... + 1538864.

It is an arithmetic number, because the mean of its divisors is an integer number (10771915).

Almost surely, 2^61553780 is an apocalyptic number.

It is an amenable number.

61553780 is an abundant number, since it is smaller than the sum of its proper divisors (67709200).

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

61553780 is a wasteful number, since it uses less digits than its factorization.

61553780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3077698 (or 3077696 counting only the distinct ones).

The product of its (nonzero) digits is 25200, while the sum is 35.

The square root of 61553780 is about 7845.6217089533. The cubic root of 61553780 is about 394.8373629442.

The spelling of 61553780 in words is "sixty-one million, five hundred fifty-three thousand, seven hundred eighty".