1645334257 has 8 divisors (see below), whose sum is σ = 1898638976. Its totient is φ = 1396593792.

The previous prime is 1645334219. The next prime is 1645334281. The reversal of 1645334257 is 7524335461.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1645334257 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1645334057) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1140288 + ... + 1141729.

It is an arithmetic number, because the mean of its divisors is an integer number (237329872).

Almost surely, 2^1645334257 is an apocalyptic number.

It is an amenable number.

1645334257 is a deficient number, since it is larger than the sum of its proper divisors (253304719).

1645334257 is a wasteful number, since it uses less digits than its factorization.

1645334257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2282127.

The product of its digits is 302400, while the sum is 40.

The square root of 1645334257 is about 40562.7200394648. The cubic root of 1645334257 is about 1180.5508911495.

The spelling of 1645334257 in words is "one billion, six hundred forty-five million, three hundred thirty-four thousand, two hundred fifty-seven".