20825831 has 12 divisors (see below), whose sum is σ = 23188536. Its totient is φ = 18592560.

The previous prime is 20825813. The next prime is 20825837. The reversal of 20825831 is 13852802.

It is not a de Polignac number, because 20825831 - 2¹⁸ = 20563687 is a prime.

It is a super-2 number, since 2×20825831² = 867430473681122, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20825794 and 20825803.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20825837) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 11660 + ... + 13326.

It is an arithmetic number, because the mean of its divisors is an integer number (1932378).

Almost surely, 2^20825831 is an apocalyptic number.

20825831 is a deficient number, since it is larger than the sum of its proper divisors (2362705).

20825831 is a wasteful number, since it uses less digits than its factorization.

20825831 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1742 (or 1711 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 29.

The square root of 20825831 is about 4563.5327324344. The cubic root of 20825831 is about 275.1275705638.

The spelling of 20825831 in words is "twenty million, eight hundred twenty-five thousand, eight hundred thirty-one".