54778509 has 12 divisors (see below), whose sum is σ = 79657500. Its totient is φ = 36273024.

The previous prime is 54778499. The next prime is 54778511. The reversal of 54778509 is 90587745.

It can be written as a sum of positive squares in 2 ways, for example, as 20520900 + 34257609 = 4530^2 + 5853^2 .

It is not a de Polignac number, because 54778509 - 2⁹ = 54777997 is a prime.

It is a super-3 number, since 3×54778509³ (a number of 24 digits) contains 333 as substring.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (54778109) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 19084 + ... + 21765.

It is an arithmetic number, because the mean of its divisors is an integer number (6638125).

Almost surely, 2^54778509 is an apocalyptic number.

It is an amenable number.

54778509 is a deficient number, since it is larger than the sum of its proper divisors (24878991).

54778509 is a wasteful number, since it uses less digits than its factorization.

54778509 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41004 (or 41001 counting only the distinct ones).

The product of its (nonzero) digits is 352800, while the sum is 45.

The square root of 54778509 is about 7401.2505024489. The cubic root of 54778509 is about 379.7840624492.

The spelling of 54778509 in words is "fifty-four million, seven hundred seventy-eight thousand, five hundred nine".