65509956 has 72 divisors (see below), whose sum is σ = 172972800. Its totient is φ = 20879040.

The previous prime is 65509933. The next prime is 65509979. The reversal of 65509956 is 65990556.

65509956 is a `hidden beast` number, since 6 + 550 + 9 + 95 + 6 = 666.

It is an interprime number because it is at equal distance from previous prime (65509933) and next prime (65509979).

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, 136525 + ... + 137003.

It is an arithmetic number, because the mean of its divisors is an integer number (2402400).

Almost surely, 2^65509956 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 65509956, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (86486400).

65509956 is an abundant number, since it is smaller than the sum of its proper divisors (107462844).

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

65509956 is a wasteful number, since it uses less digits than its factorization.

65509956 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 649 (or 644 counting only the distinct ones).

The product of its (nonzero) digits is 364500, while the sum is 45.

The square root of 65509956 is about 8093.8220884821. The cubic root of 65509956 is about 403.1213216899.

The spelling of 65509956 in words is "sixty-five million, five hundred nine thousand, nine hundred fifty-six".