20195131 has 4 divisors (see below), whose sum is σ = 22031064. Its totient is φ = 18359200.

The previous prime is 20195111. The next prime is 20195137. The reversal of 20195131 is 13159102.

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 20195131 - 2⁹ = 20194619 is a prime.

It is a super-2 number, since 2×20195131² = 815686632214322, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20195137) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 917950 + ... + 917971.

It is an arithmetic number, because the mean of its divisors is an integer number (5507766).

Almost surely, 2^20195131 is an apocalyptic number.

20195131 is a deficient number, since it is larger than the sum of its proper divisors (1835933).

20195131 is a wasteful number, since it uses less digits than its factorization.

20195131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1835932.

The product of its (nonzero) digits is 270, while the sum is 22.

The square root of 20195131 is about 4493.8993090633. The cubic root of 20195131 is about 272.3216845366.

The spelling of 20195131 in words is "twenty million, one hundred ninety-five thousand, one hundred thirty-one".