65215820 has 12 divisors (see below), whose sum is σ = 136953264. Its totient is φ = 26086320.

The previous prime is 65215819. The next prime is 65215823. The reversal of 65215820 is 2851256.

It is not an unprimeable number, because it can be changed into a prime (65215823) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1630376 + ... + 1630415.

It is an arithmetic number, because the mean of its divisors is an integer number (11412772).

Almost surely, 2^65215820 is an apocalyptic number.

It is an amenable number.

65215820 is an abundant number, since it is smaller than the sum of its proper divisors (71737444).

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

65215820 is a wasteful number, since it uses less digits than its factorization.

65215820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3260800 (or 3260798 counting only the distinct ones).

The product of its (nonzero) digits is 4800, while the sum is 29.

The square root of 65215820 is about 8075.6312446768. The cubic root of 65215820 is about 402.5170858069.

The spelling of 65215820 in words is "sixty-five million, two hundred fifteen thousand, eight hundred twenty".