20451131 has 2 divisors, whose sum is σ = 20451132. Its totient is φ = 20451130.

The previous prime is 20451127. The next prime is 20451181. The reversal of 20451131 is 13115402.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20451131 - 2² = 20451127 is a prime.

It is a super-2 number, since 2×20451131² = 836497518358322, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (20451181) 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 as a sum of consecutive naturals, namely, 10225565 + 10225566.

It is an arithmetic number, because the mean of its divisors is an integer number (10225566).

Almost surely, 2^20451131 is an apocalyptic number.

20451131 is a deficient number, since it is larger than the sum of its proper divisors (1).

20451131 is an equidigital number, since it uses as much as digits as its factorization.

20451131 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 120, while the sum is 17.

The square root of 20451131 is about 4522.2926707589. The cubic root of 20451131 is about 273.4675355589.

Adding to 20451131 its reverse (13115402), we get a palindrome (33566533).

The spelling of 20451131 in words is "twenty million, four hundred fifty-one thousand, one hundred thirty-one".