65221937520100 has 81 divisors (see below), whose sum is σ = 144615401782537. Its totient is φ = 25532208702880.

The previous prime is 65221937520097. The next prime is 65221937520101. The reversal of 65221937520100 is 102573912256.

It is a happy number.

The square root of 65221937520100 is 8076010.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 23479897507236 + 41742040012864 = 4845606^2 + 6460808^2 .

It is a super-2 number, since 2×65221937520100² (a number of 28 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (65221937520101) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 3795716109 + ... + 3795733291.

Almost surely, 2^{65221937520100} is an apocalyptic number.

65221937520100 is the 8076010-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 65221937520100

65221937520100 is an abundant number, since it is smaller than the sum of its proper divisors (79393464262437).

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

65221937520100 is an frugal number, since it uses more digits than its factorization.

65221937520100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34474 (or 17237 counting only the distinct ones).

The product of its (nonzero) digits is 226800, while the sum is 43.

The spelling of 65221937520100 in words is "sixty-five trillion, two hundred twenty-one billion, nine hundred thirty-seven million, five hundred twenty thousand, one hundred".