821258253 has 48 divisors (see below), whose sum is σ = 1297520640. Its totient is φ = 498451968.

The previous prime is 821258237. The next prime is 821258281. The reversal of 821258253 is 352852128.

821258253 is a `hidden beast` number, since 8 + 21 + 2 + 582 + 53 = 666.

It is not a de Polignac number, because 821258253 - 2⁴ = 821258237 is a prime.

It is a super-2 number, since 2×821258253² = 1348930236241224018, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (821258353) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1352676 + ... + 1353282.

It is an arithmetic number, because the mean of its divisors is an integer number (27031680).

Almost surely, 2^821258253 is an apocalyptic number.

It is an amenable number.

821258253 is a deficient number, since it is larger than the sum of its proper divisors (476262387).

821258253 is a wasteful number, since it uses less digits than its factorization.

821258253 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 906 (or 903 counting only the distinct ones).

The product of its digits is 38400, while the sum is 36.

The square root of 821258253 is about 28657.6037553735. The cubic root of 821258253 is about 936.4686625420.

The spelling of 821258253 in words is "eight hundred twenty-one million, two hundred fifty-eight thousand, two hundred fifty-three".