20901247 has 2 divisors, whose sum is σ = 20901248. Its totient is φ = 20901246.

The previous prime is 20901241. The next prime is 20901259. The reversal of 20901247 is 74210902.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20901247 - 2²³ = 12512639 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20901241) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10450623 + 10450624.

It is an arithmetic number, because the mean of its divisors is an integer number (10450624).

Almost surely, 2^20901247 is an apocalyptic number.

20901247 is a deficient number, since it is larger than the sum of its proper divisors (1).

20901247 is an equidigital number, since it uses as much as digits as its factorization.

20901247 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1008, while the sum is 25.

The square root of 20901247 is about 4571.7881621965. The cubic root of 20901247 is about 275.4592744172.

The spelling of 20901247 in words is "twenty million, nine hundred one thousand, two hundred forty-seven".