1645712604 has 18 divisors (see below), whose sum is σ = 4159995840. Its totient is φ = 548570856.

The previous prime is 1645712597. The next prime is 1645712623. The reversal of 1645712604 is 4062175461.

1645712604 is a `hidden beast` number, since 1 + 6 + 45 + 7 + 1 + 2 + 604 = 666.

It is a tau number, because it is divible by the number of its divisors (18).

It is a Harshad number since it is a multiple of its sum of digits (36), and also a Moran number because the ratio is a prime number: 45714239 = 1645712604 / (1 + 6 + 4 + 5 + 7 + 1 + 2 + 6 + 0 + 4).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 22857084 + ... + 22857155.

It is an arithmetic number, because the mean of its divisors is an integer number (231110880).

Almost surely, 2^1645712604 is an apocalyptic number.

It is an amenable number.

1645712604 is an abundant number, since it is smaller than the sum of its proper divisors (2514283236).

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

1645712604 is a wasteful number, since it uses less digits than its factorization.

1645712604 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45714249 (or 45714244 counting only the distinct ones).

The product of its (nonzero) digits is 40320, while the sum is 36.

The square root of 1645712604 is about 40567.3834995554. The cubic root of 1645712604 is about 1180.6413740112.

The spelling of 1645712604 in words is "one billion, six hundred forty-five million, seven hundred twelve thousand, six hundred four".