61505860 has 72 divisors (see below), whose sum is σ = 144619776. Its totient is φ = 21939840.

The previous prime is 61505837. The next prime is 61505879. The reversal of 61505860 is 6850516.

It is a Harshad number since it is a multiple of its sum of digits (31).

It is a nialpdrome in base 13.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 104487 + ... + 105073.

It is an arithmetic number, because the mean of its divisors is an integer number (2008608).

Almost surely, 2^61505860 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61505860, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (72309888).

61505860 is an abundant number, since it is smaller than the sum of its proper divisors (83113916).

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

61505860 is a wasteful number, since it uses less digits than its factorization.

61505860 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 653 (or 638 counting only the distinct ones).

The product of its (nonzero) digits is 7200, while the sum is 31.

The square root of 61505860 is about 7842.5671817333. The cubic root of 61505860 is about 394.7348752307.

The spelling of 61505860 in words is "sixty-one million, five hundred five thousand, eight hundred sixty".