472778809 has 2 divisors, whose sum is σ = 472778810. Its totient is φ = 472778808.

The previous prime is 472778797. The next prime is 472778819. The reversal of 472778809 is 908877274.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 384042409 + 88736400 = 19597^2 + 9420^2 .

It is a cyclic number.

It is not a de Polignac number, because 472778809 - 2²¹ = 470681657 is a prime.

It is equal to p_24994879 and since 472778809 and 24994879 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (472778819) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 236389404 + 236389405.

It is an arithmetic number, because the mean of its divisors is an integer number (236389405).

Almost surely, 2^472778809 is an apocalyptic number.

It is an amenable number.

472778809 is a deficient number, since it is larger than the sum of its proper divisors (1).

472778809 is an equidigital number, since it uses as much as digits as its factorization.

472778809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1580544, while the sum is 52.

The square root of 472778809 is about 21743.4773897829. The cubic root of 472778809 is about 779.0272824131.

The spelling of 472778809 in words is "four hundred seventy-two million, seven hundred seventy-eight thousand, eight hundred nine".