1644792457 has 12 divisors (see below), whose sum is σ = 2087269776. Its totient is φ = 1281656040.

The previous prime is 1644792439. The next prime is 1644792463. The reversal of 1644792457 is 7542974461.

It is a happy number.

It is not a de Polignac number, because 1644792457 - 2⁷ = 1644792329 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (49).

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1644792457.

It is not an unprimeable number, because it can be changed into a prime (1644792427) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1525243 + ... + 1526320.

It is an arithmetic number, because the mean of its divisors is an integer number (173939148).

Almost surely, 2^1644792457 is an apocalyptic number.

It is an amenable number.

1644792457 is a deficient number, since it is larger than the sum of its proper divisors (442477319).

1644792457 is a wasteful number, since it uses less digits than its factorization.

1644792457 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3051588 (or 3051581 counting only the distinct ones).

The product of its digits is 1693440, while the sum is 49.

The square root of 1644792457 is about 40556.0409433663. The cubic root of 1644792457 is about 1180.4212938370.

The spelling of 1644792457 in words is "one billion, six hundred forty-four million, seven hundred ninety-two thousand, four hundred fifty-seven".