61517664 has 96 divisors (see below), whose sum is σ = 193263840. Its totient is φ = 18925056.

The previous prime is 61517653. The next prime is 61517699. The reversal of 61517664 is 46671516.

It is a tau number, because it is divible by the number of its divisors (96).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8494 + ... + 13970.

It is an arithmetic number, because the mean of its divisors is an integer number (2013165).

Almost surely, 2^61517664 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 61517664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (96631920).

61517664 is an abundant number, since it is smaller than the sum of its proper divisors (131746176).

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

61517664 is a wasteful number, since it uses less digits than its factorization.

61517664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5509 (or 5495 counting only the distinct ones).

The product of its digits is 30240, while the sum is 36.

The square root of 61517664 is about 7843.3197053289. The cubic root of 61517664 is about 394.7601256834.

The spelling of 61517664 in words is "sixty-one million, five hundred seventeen thousand, six hundred sixty-four".