20890507 has 4 divisors (see below), whose sum is σ = 22789656. Its totient is φ = 18991360.

The previous prime is 20890489. The next prime is 20890511. The reversal of 20890507 is 70509802.

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 20890507 - 2⁷ = 20890379 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20899507) 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, 949558 + ... + 949579.

It is an arithmetic number, because the mean of its divisors is an integer number (5697414).

Almost surely, 2^20890507 is an apocalyptic number.

20890507 is a deficient number, since it is larger than the sum of its proper divisors (1899149).

20890507 is a wasteful number, since it uses less digits than its factorization.

20890507 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1899148.

The product of its (nonzero) digits is 5040, while the sum is 31.

The square root of 20890507 is about 4570.6134161620. The cubic root of 20890507 is about 275.4120852156.

The spelling of 20890507 in words is "twenty million, eight hundred ninety thousand, five hundred seven".