1978688188860 has 48 divisors (see below), whose sum is σ = 5592105703296. Its totient is φ = 522718871872.

The previous prime is 1978688188847. The next prime is 1978688188877. The reversal of 1978688188860 is 688818868791.

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, 154097022 + ... + 154109861.

It is an arithmetic number, because the mean of its divisors is an integer number (116502202152).

Almost surely, 2^{1978688188860} is an apocalyptic number.

1978688188860 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1978688188860 is an abundant number, since it is smaller than the sum of its proper divisors (3613417514436).

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

1978688188860 is a wasteful number, since it uses less digits than its factorization.

1978688188860 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 308207002 (or 308207000 counting only the distinct ones).

The product of its (nonzero) digits is 594542592, while the sum is 78.

The spelling of 1978688188860 in words is "one trillion, nine hundred seventy-eight billion, six hundred eighty-eight million, one hundred eighty-eight thousand, eight hundred sixty".