20912331 has 16 divisors (see below), whose sum is σ = 32019840. Its totient is φ = 12006720.

The previous prime is 20912317. The next prime is 20912341. The reversal of 20912331 is 13321902.

It is a happy number.

It is not a de Polignac number, because 20912331 - 2¹⁰ = 20911307 is a prime.

It is a super-2 number, since 2×20912331² = 874651175707122, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 20912298 and 20912307.

It is not an unprimeable number, because it can be changed into a prime (20912341) 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, 16050 + ... + 17303.

It is an arithmetic number, because the mean of its divisors is an integer number (2001240).

Almost surely, 2^20912331 is an apocalyptic number.

20912331 is a deficient number, since it is larger than the sum of its proper divisors (11107509).

20912331 is a wasteful number, since it uses less digits than its factorization.

20912331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33386.

The product of its (nonzero) digits is 324, while the sum is 21.

The square root of 20912331 is about 4573.0002186748. Note that the first 3 decimals coincide. The cubic root of 20912331 is about 275.5079581321.

The spelling of 20912331 in words is "twenty million, nine hundred twelve thousand, three hundred thirty-one".