20974999 has 2 divisors, whose sum is σ = 20975000. Its totient is φ = 20974998.

The previous prime is 20974969. The next prime is 20975051. The reversal of 20974999 is 99947902.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20974999 - 2⁹ = 20974487 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20974969) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10487499 + 10487500.

It is an arithmetic number, because the mean of its divisors is an integer number (10487500).

Almost surely, 2^20974999 is an apocalyptic number.

20974999 is a deficient number, since it is larger than the sum of its proper divisors (1).

20974999 is an equidigital number, since it uses as much as digits as its factorization.

20974999 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 367416, while the sum is 49.

The square root of 20974999 is about 4579.8470498478. The cubic root of 20974999 is about 275.7828886636.

The spelling of 20974999 in words is "twenty million, nine hundred seventy-four thousand, nine hundred ninety-nine".