921194924521 has 9 divisors (see below), whose sum is σ = 926178927429. Its totient is φ = 916237614336.

The previous prime is 921194924473. The next prime is 921194924537. The reversal of 921194924521 is 125429491129.

The square root of 921194924521 is 959789.

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

It can be written as a sum of positive squares in 4 ways, for example, as 13176514521 + 908018410000 = 114789^2 + 952900^2 .

It is not a de Polignac number, because 921194924521 - 2⁹ = 921194924009 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (921194924821) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 185236791 + ... + 185241763.

Almost surely, 2^921194924521 is an apocalyptic number.

921194924521 is the 959789-th square number.

921194924521 is the 479895-th centered octagonal number.

It is an amenable number.

921194924521 is a deficient number, since it is larger than the sum of its proper divisors (4984002908).

921194924521 is an frugal number, since it uses more digits than its factorization.

921194924521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10332 (or 5166 counting only the distinct ones).

The product of its digits is 466560, while the sum is 49.

Multiplying 921194924521 by its sum of digits (49), we get a square (45138551301529 = 6718523²).

The spelling of 921194924521 in words is "nine hundred twenty-one billion, one hundred ninety-four million, nine hundred twenty-four thousand, five hundred twenty-one".