921805253 has 4 divisors (see below), whose sum is σ = 922401900. Its totient is φ = 921208608.

The previous prime is 921805217. The next prime is 921805267. The reversal of 921805253 is 352508129.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 352508129 = 18517 ⋅19037.

It can be written as a sum of positive squares in 2 ways, for example, as 374151649 + 547653604 = 19343^2 + 23402^2 .

It is a cyclic number.

It is not a de Polignac number, because 921805253 - 2⁶ = 921805189 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (921805853) 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, 296000 + ... + 299097.

It is an arithmetic number, because the mean of its divisors is an integer number (230600475).

Almost surely, 2^921805253 is an apocalyptic number.

It is an amenable number.

921805253 is a deficient number, since it is larger than the sum of its proper divisors (596647).

921805253 is a wasteful number, since it uses less digits than its factorization.

921805253 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 596646.

The product of its (nonzero) digits is 21600, while the sum is 35.

The square root of 921805253 is about 30361.2459065830. The cubic root of 921805253 is about 973.2245587327.

The spelling of 921805253 in words is "nine hundred twenty-one million, eight hundred five thousand, two hundred fifty-three".