20163931 has 2 divisors, whose sum is σ = 20163932. Its totient is φ = 20163930.

The previous prime is 20163911. The next prime is 20163991. The reversal of 20163931 is 13936102.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20163931 is a prime.

It is a super-2 number, since 2×20163931² = 813168226745522, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 20163896 and 20163905.

It is not a weakly prime, because it can be changed into another prime (20163911) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10081965 + 10081966.

It is an arithmetic number, because the mean of its divisors is an integer number (10081966).

Almost surely, 2^20163931 is an apocalyptic number.

20163931 is a deficient number, since it is larger than the sum of its proper divisors (1).

20163931 is an equidigital number, since it uses as much as digits as its factorization.

20163931 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 972, while the sum is 25.

The square root of 20163931 is about 4490.4265944340. The cubic root of 20163931 is about 272.1813732280.

The spelling of 20163931 in words is "twenty million, one hundred sixty-three thousand, nine hundred thirty-one".