213592789921 has 27 divisors (see below), whose sum is σ = 251292816243. Its totient is φ = 181019220480.

The previous prime is 213592789919. The next prime is 213592789933. The reversal of 213592789921 is 129987295312.

It is a happy number.

The square root of 213592789921 is 462161.

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., 192799149921 + 20793640000 = 439089^2 + 144200^2 .

It is not a de Polignac number, because 213592789921 - 2¹ = 213592789919 is a prime.

It is not an unprimeable number, because it can be changed into a prime (213592789901) 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, 333217761 + ... + 333218401.

Almost surely, 2^213592789921 is an apocalyptic number.

213592789921 is the 462161-st square number.

213592789921 is the 231081-st centered octagonal number.

It is an amenable number.

213592789921 is a deficient number, since it is larger than the sum of its proper divisors (37700026322).

213592789921 is an frugal number, since it uses more digits than its factorization.

213592789921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1502 (or 751 counting only the distinct ones).

The product of its digits is 4898880, while the sum is 58.

The spelling of 213592789921 in words is "two hundred thirteen billion, five hundred ninety-two million, seven hundred eighty-nine thousand, nine hundred twenty-one".