61561550 has 12 divisors (see below), whose sum is σ = 114504576. Its totient is φ = 24624600.

The previous prime is 61561529. The next prime is 61561561. The reversal of 61561550 is 5516516.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 615566 + ... + 615665.

It is an arithmetic number, because the mean of its divisors is an integer number (9542048).

Almost surely, 2^61561550 is an apocalyptic number.

61561550 is a deficient number, since it is larger than the sum of its proper divisors (52943026).

61561550 is a wasteful number, since it uses less digits than its factorization.

61561550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1231243 (or 1231238 counting only the distinct ones).

The product of its (nonzero) digits is 4500, while the sum is 29.

The square root of 61561550 is about 7846.1168739702. The cubic root of 61561550 is about 394.8539758271.

The spelling of 61561550 in words is "sixty-one million, five hundred sixty-one thousand, five hundred fifty".