61645554 has 12 divisors (see below), whose sum is σ = 133565406. Its totient is φ = 20548512.

The previous prime is 61645471. The next prime is 61645627. The reversal of 61645554 is 45554616.

61645554 is a `hidden beast` number, since 6 + 1 + 645 + 5 + 5 + 4 = 666.

It can be written as a sum of positive squares in only one way, i.e., 60140025 + 1505529 = 7755^2 + 1227^2 .

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

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, 1712359 + ... + 1712394.

Almost surely, 2^61645554 is an apocalyptic number.

61645554 is an abundant number, since it is smaller than the sum of its proper divisors (71919852).

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

61645554 is a wasteful number, since it uses less digits than its factorization.

61645554 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3424761 (or 3424758 counting only the distinct ones).

The product of its digits is 72000, while the sum is 36.

The square root of 61645554 is about 7851.4682703301. The cubic root of 61645554 is about 395.0334939285.

The spelling of 61645554 in words is "sixty-one million, six hundred forty-five thousand, five hundred fifty-four".