56661540 has 48 divisors (see below), whose sum is σ = 170858688. Its totient is φ = 13947264.

The previous prime is 56661533. The next prime is 56661547. The reversal of 56661540 is 4516665.

It is an interprime number because it is at equal distance from previous prime (56661533) and next prime (56661547).

It is not an unprimeable number, because it can be changed into a prime (56661547) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 35542 + ... + 37101.

It is an arithmetic number, because the mean of its divisors is an integer number (3559556).

Almost surely, 2^56661540 is an apocalyptic number.

It is an amenable number.

56661540 is an abundant number, since it is smaller than the sum of its proper divisors (114197148).

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

56661540 is a wasteful number, since it uses less digits than its factorization.

56661540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72668 (or 72666 counting only the distinct ones).

The product of its (nonzero) digits is 21600, while the sum is 33.

The square root of 56661540 is about 7527.3860004652. The cubic root of 56661540 is about 384.0868672834.

The spelling of 56661540 in words is "fifty-six million, six hundred sixty-one thousand, five hundred forty".