1265888642 has 16 divisors (see below), whose sum is σ = 2007513600. Its totient is φ = 597008880.

The previous prime is 1265888621. The next prime is 1265888669. The reversal of 1265888642 is 2468885621.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 64034 + ... + 81437.

It is an arithmetic number, because the mean of its divisors is an integer number (125469600).

Almost surely, 2^1265888642 is an apocalyptic number.

1265888642 is a deficient number, since it is larger than the sum of its proper divisors (741624958).

1265888642 is a wasteful number, since it uses less digits than its factorization.

1265888642 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 145721.

The product of its digits is 1474560, while the sum is 50.

The square root of 1265888642 is about 35579.3288582008. The cubic root of 1265888642 is about 1081.7622811699.

The spelling of 1265888642 in words is "one billion, two hundred sixty-five million, eight hundred eighty-eight thousand, six hundred forty-two".