1645261256 has 32 divisors (see below), whose sum is σ = 3188635200. Its totient is φ = 795416640.

The previous prime is 1645261253. The next prime is 1645261259. The reversal of 1645261256 is 6521625461.

It is an interprime number because it is at equal distance from previous prime (1645261253) and next prime (1645261259).

It is not an unprimeable number, because it can be changed into a prime (1645261253) 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 7 ways as a sum of consecutive naturals, for example, 221 + ... + 57363.

It is an arithmetic number, because the mean of its divisors is an integer number (99644850).

Almost surely, 2^1645261256 is an apocalyptic number.

It is an amenable number.

1645261256 is a deficient number, since it is larger than the sum of its proper divisors (1543373944).

1645261256 is a wasteful number, since it uses less digits than its factorization.

1645261256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57269 (or 57265 counting only the distinct ones).

The product of its digits is 86400, while the sum is 38.

The square root of 1645261256 is about 40561.8201761213. The cubic root of 1645261256 is about 1180.5334311370.

The spelling of 1645261256 in words is "one billion, six hundred forty-five million, two hundred sixty-one thousand, two hundred fifty-six".