54778309 has 6 divisors (see below), whose sum is σ = 55834226. Its totient is φ = 53742000.

The previous prime is 54778307. The next prime is 54778319. The reversal of 54778309 is 90387745.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 19554084 + 35224225 = 4422^2 + 5935^2 .

It is not a de Polignac number, because 54778309 - 2¹ = 54778307 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (54778307) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 6942 + ... + 12559.

Almost surely, 2^54778309 is an apocalyptic number.

It is an amenable number.

54778309 is a deficient number, since it is larger than the sum of its proper divisors (1055917).

54778309 is an equidigital number, since it uses as much as digits as its factorization.

54778309 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19607 (or 19554 counting only the distinct ones).

The product of its (nonzero) digits is 211680, while the sum is 43.

The square root of 54778309 is about 7401.2369912063. The cubic root of 54778309 is about 379.7836002429.

The spelling of 54778309 in words is "fifty-four million, seven hundred seventy-eight thousand, three hundred nine".