61535540 has 24 divisors (see below), whose sum is σ = 140972832. Its totient is φ = 22376480.

The previous prime is 61535531. The next prime is 61535609. The reversal of 61535540 is 4553516.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 139634 + ... + 140073.

It is an arithmetic number, because the mean of its divisors is an integer number (5873868).

Almost surely, 2^61535540 is an apocalyptic number.

It is an amenable number.

61535540 is an abundant number, since it is smaller than the sum of its proper divisors (79437292).

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

61535540 is a wasteful number, since it uses less digits than its factorization.

61535540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 279727 (or 279725 counting only the distinct ones).

The product of its (nonzero) digits is 9000, while the sum is 29.

The square root of 61535540 is about 7844.4591910469. The cubic root of 61535540 is about 394.7983588679.

The spelling of 61535540 in words is "sixty-one million, five hundred thirty-five thousand, five hundred forty".