61615616 has 40 divisors (see below), whose sum is σ = 130371120. Its totient is φ = 28991488.

The previous prime is 61615573. The next prime is 61615663. The reversal of 61615616 is 61651616.

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5165 + ... + 12243.

It is an arithmetic number, because the mean of its divisors is an integer number (3259278).

Almost surely, 2^61615616 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 61615616, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (65185560).

61615616 is an abundant number, since it is smaller than the sum of its proper divisors (68755504).

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

61615616 is an equidigital number, since it uses as much as digits as its factorization.

61615616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7114 (or 7098 counting only the distinct ones).

The product of its digits is 6480, while the sum is 32.

The square root of 61615616 is about 7849.5615164161. The cubic root of 61615616 is about 394.9695345835.

The spelling of 61615616 in words is "sixty-one million, six hundred fifteen thousand, six hundred sixteen".