20474309 has 2 divisors, whose sum is σ = 20474310. Its totient is φ = 20474308.

The previous prime is 20474303. The next prime is 20474317. The reversal of 20474309 is 90347402.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18062500 + 2411809 = 4250^2 + 1553^2 .

It is a cyclic number.

It is not a de Polignac number, because 20474309 - 2⁸ = 20474053 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20474303) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10237154 + 10237155.

It is an arithmetic number, because the mean of its divisors is an integer number (10237155).

Almost surely, 2^20474309 is an apocalyptic number.

It is an amenable number.

20474309 is a deficient number, since it is larger than the sum of its proper divisors (1).

20474309 is an equidigital number, since it uses as much as digits as its factorization.

20474309 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6048, while the sum is 29.

The square root of 20474309 is about 4524.8545832988. The cubic root of 20474309 is about 273.5708067426.

The spelling of 20474309 in words is "twenty million, four hundred seventy-four thousand, three hundred nine".