20847371 has 2 divisors, whose sum is σ = 20847372. Its totient is φ = 20847370.

The previous prime is 20847353. The next prime is 20847377. The reversal of 20847371 is 17374802.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20847371 - 2²² = 16653067 is a prime.

It is a super-2 number, since 2×20847371² = 869225755223282, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (20847377) 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, 10423685 + 10423686.

It is an arithmetic number, because the mean of its divisors is an integer number (10423686).

Almost surely, 2^20847371 is an apocalyptic number.

20847371 is a deficient number, since it is larger than the sum of its proper divisors (1).

20847371 is an equidigital number, since it uses as much as digits as its factorization.

20847371 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 9408, while the sum is 32.

The square root of 20847371 is about 4565.8921362643. The cubic root of 20847371 is about 275.2223920043. Note that the first 3 decimals are identical.

The spelling of 20847371 in words is "twenty million, eight hundred forty-seven thousand, three hundred seventy-one".