61543881 has 48 divisors (see below), whose sum is σ = 106730624. Its totient is φ = 34712064.

The previous prime is 61543877. The next prime is 61543943. The reversal of 61543881 is 18834516.

61543881 is a `hidden beast` number, since 615 + 4 + 38 + 8 + 1 = 666.

It is not a de Polignac number, because 61543881 - 2² = 61543877 is a prime.

It is a super-2 number, since 2×61543881² = 7575298577084322, which contains 22 as substring.

Its product of digits (23040) is a multiple of the sum of its prime divisors (480).

It is not an unprimeable number, because it can be changed into a prime (61543861) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 164811 + ... + 165183.

Almost surely, 2^61543881 is an apocalyptic number.

It is an amenable number.

61543881 is a deficient number, since it is larger than the sum of its proper divisors (45186743).

61543881 is an equidigital number, since it uses as much as digits as its factorization.

61543881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 492 (or 480 counting only the distinct ones).

The product of its digits is 23040, while the sum is 36.

The square root of 61543881 is about 7844.9908221744. The cubic root of 61543881 is about 394.8161960632.

The spelling of 61543881 in words is "sixty-one million, five hundred forty-three thousand, eight hundred eighty-one".