1285913640 has 64 divisors (see below), whose sum is σ = 4208448960. Its totient is φ = 311736320.

The previous prime is 1285913639. The next prime is 1285913653. The reversal of 1285913640 is 463195821.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 485769 + ... + 488408.

It is an arithmetic number, because the mean of its divisors is an integer number (65757015).

Almost surely, 2^1285913640 is an apocalyptic number.

1285913640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1285913640 is an abundant number, since it is smaller than the sum of its proper divisors (2922535320).

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

1285913640 is a wasteful number, since it uses less digits than its factorization.

1285913640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 974202 (or 974198 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 39.

The square root of 1285913640 is about 35859.6380349830. The cubic root of 1285913640 is about 1087.4365707489.

It can be divided in two parts, 128591 and 3640, that added together give a palindrome (132231).

The spelling of 1285913640 in words is "one billion, two hundred eighty-five million, nine hundred thirteen thousand, six hundred forty".