53219721636 has 27 divisors (see below), whose sum is σ = 134531128641. Its totient is φ = 17739445824.

The previous prime is 53219721521. The next prime is 53219721661. The reversal of 53219721636 is 63612791235.

The square root of 53219721636 is 230694.

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

53219721636 is a `hidden beast` number, since 5 + 3 + 2 + 1 + 9 + 7 + 2 + 1 + 636 = 666.

It can be written as a sum of positive squares in only one way, i.e., 466819236 + 52752902400 = 21606^2 + 229680^2 .

It is a junction number, because it is equal to n+sod(n) for n = 53219721591 and 53219721600.

It is an unprimeable number.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 1364940 + ... + 1403388.

Almost surely, 2^53219721636 is an apocalyptic number.

53219721636 is the 230694-th square number.

It is an amenable number.

53219721636 is an abundant number, since it is smaller than the sum of its proper divisors (81311407005).

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

53219721636 is an frugal number, since it uses more digits than its factorization.

53219721636 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 76908 (or 38454 counting only the distinct ones).

The product of its digits is 408240, while the sum is 45.

The spelling of 53219721636 in words is "fifty-three billion, two hundred nineteen million, seven hundred twenty-one thousand, six hundred thirty-six".