7861978040 has 64 divisors (see below), whose sum is σ = 20425003200. Its totient is φ = 2667737088.

The previous prime is 7861978009. The next prime is 7861978073. The reversal of 7861978040 is 408791687.

It is a self number, because there is not a number n which added to its sum of digits gives 7861978040.

It is a congruent number.

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, 117575 + ... + 171894.

It is an arithmetic number, because the mean of its divisors is an integer number (319140675).

Almost surely, 2^7861978040 is an apocalyptic number.

7861978040 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is an amenable number.

7861978040 is an abundant number, since it is smaller than the sum of its proper divisors (12563025160).

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

7861978040 is a wasteful number, since it uses less digits than its factorization.

7861978040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 289584 (or 289580 counting only the distinct ones).

The product of its (nonzero) digits is 677376, while the sum is 50.

The square root of 7861978040 is about 88667.7959577207. The cubic root of 7861978040 is about 1988.4313825672.

The spelling of 7861978040 in words is "seven billion, eight hundred sixty-one million, nine hundred seventy-eight thousand, forty".