1296242640 has 480 divisors, whose sum is σ = 5504219136. Its totient is φ = 265559040.

The previous prime is 1296242621. The next prime is 1296242659. The reversal of 1296242640 is 462426921.

1296242640 is a `hidden beast` number, since 1 + 2 + 9 + 6 + 2 + 4 + 2 + 640 = 666.

It is an interprime number because it is at equal distance from previous prime (1296242621) and next prime (1296242659).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 1296242595 and 1296242604.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 5710207 + ... + 5710433.

Almost surely, 2^1296242640 is an apocalyptic number.

1296242640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1296242640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2752109568).

1296242640 is an abundant number, since it is smaller than the sum of its proper divisors (4207976496).

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

1296242640 is a wasteful number, since it uses less digits than its factorization.

1296242640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 367 (or 358 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 36.

The square root of 1296242640 is about 36003.3698422800. The cubic root of 1296242640 is about 1090.3403925245.

The spelling of 1296242640 in words is "one billion, two hundred ninety-six million, two hundred forty-two thousand, six hundred forty".