684099045 has 54 divisors (see below), whose sum is σ = 1381847922. Its totient is φ = 312169536.

The previous prime is 684098969. The next prime is 684099061. The reversal of 684099045 is 540990486.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 17994564 + 666104481 = 4242^2 + 25809^2 .

It is not a de Polignac number, because 684099045 - 2¹⁴ = 684082661 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 53 ways as a sum of consecutive naturals, for example, 1227907 + ... + 1228463.

Almost surely, 2^684099045 is an apocalyptic number.

It is an amenable number.

684099045 is an abundant number, since it is smaller than the sum of its proper divisors (697748877).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

684099045 is an equidigital number, since it uses as much as digits as its factorization.

684099045 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1139 (or 572 counting only the distinct ones).

The product of its (nonzero) digits is 311040, while the sum is 45.

The square root of 684099045 is about 26155.2871328150. The cubic root of 684099045 is about 881.1293373348.

Multiplying 684099045 by its sum of digits (45), we get a square (30784457025 = 175455²).

684099045 divided by its sum of digits (45) gives a square (15202201 = 3899²).

The spelling of 684099045 in words is "six hundred eighty-four million, ninety-nine thousand, forty-five".