20745831 has 16 divisors (see below), whose sum is σ = 29528064. Its totient is φ = 12910464.

The previous prime is 20745799. The next prime is 20745833. The reversal of 20745831 is 13854702.

It is not a de Polignac number, because 20745831 - 2⁵ = 20745799 is a prime.

It is a super-2 number, since 2×20745831² = 860779007761122, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20745833) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4876 + ... + 8078.

It is an arithmetic number, because the mean of its divisors is an integer number (1845504).

Almost surely, 2^20745831 is an apocalyptic number.

20745831 is a deficient number, since it is larger than the sum of its proper divisors (8782233).

20745831 is a wasteful number, since it uses less digits than its factorization.

20745831 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3350.

The product of its (nonzero) digits is 6720, while the sum is 30.

The square root of 20745831 is about 4554.7591593848. The cubic root of 20745831 is about 274.7748283506.

The spelling of 20745831 in words is "twenty million, seven hundred forty-five thousand, eight hundred thirty-one".