20379891 has 16 divisors (see below), whose sum is σ = 31223808. Its totient is φ = 11582400.

The previous prime is 20379841. The next prime is 20379899. The reversal of 20379891 is 19897302.

It is not a de Polignac number, because 20379891 - 2¹⁰ = 20378867 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20379899) 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, 1471 + ... + 6551.

It is an arithmetic number, because the mean of its divisors is an integer number (1951488).

Almost surely, 2^20379891 is an apocalyptic number.

20379891 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

20379891 is a deficient number, since it is larger than the sum of its proper divisors (10843917).

20379891 is a wasteful number, since it uses less digits than its factorization.

20379891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5282.

The product of its (nonzero) digits is 27216, while the sum is 39.

The square root of 20379891 is about 4514.4092636800. The cubic root of 20379891 is about 273.1496315062.

The spelling of 20379891 in words is "twenty million, three hundred seventy-nine thousand, eight hundred ninety-one".