61138520 has 16 divisors (see below), whose sum is σ = 137561760. Its totient is φ = 24455392.

The previous prime is 61138513. The next prime is 61138543. The reversal of 61138520 is 2583116.

61138520 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a self number, because there is not a number n which added to its sum of digits gives 61138520.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 764192 + ... + 764271.

It is an arithmetic number, because the mean of its divisors is an integer number (8597610).

Almost surely, 2^61138520 is an apocalyptic number.

It is an amenable number.

61138520 is an abundant number, since it is smaller than the sum of its proper divisors (76423240).

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

61138520 is a wasteful number, since it uses less digits than its factorization.

61138520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1528474 (or 1528470 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 26.

The square root of 61138520 is about 7819.1124816056. The cubic root of 61138520 is about 393.9474622243.

The spelling of 61138520 in words is "sixty-one million, one hundred thirty-eight thousand, five hundred twenty".