20930291 has 4 divisors (see below), whose sum is σ = 21047400. Its totient is φ = 20813184.

The previous prime is 20930269. The next prime is 20930317. The reversal of 20930291 is 19203902.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20930291 - 2⁶ = 20930227 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20930291.

It is not an unprimeable number, because it can be changed into a prime (20930201) 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, 58286 + ... + 58643.

It is an arithmetic number, because the mean of its divisors is an integer number (5261850).

Almost surely, 2^20930291 is an apocalyptic number.

20930291 is a deficient number, since it is larger than the sum of its proper divisors (117109).

20930291 is a wasteful number, since it uses less digits than its factorization.

20930291 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 117108.

The product of its (nonzero) digits is 972, while the sum is 26.

The square root of 20930291 is about 4574.9634971221. The cubic root of 20930291 is about 275.5868064614.

The spelling of 20930291 in words is "twenty million, nine hundred thirty thousand, two hundred ninety-one".