1978552117850 has 144 divisors (see below), whose sum is σ = 4778727329376. Its totient is φ = 602349552000.

The previous prime is 1978552117847. The next prime is 1978552117879. The reversal of 1978552117850 is 587112558791.

It is a self number, because there is not a number n which added to its sum of digits gives 1978552117850.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 305180 + ... + 2012520.

It is an arithmetic number, because the mean of its divisors is an integer number (33185606454).

Almost surely, 2^{1978552117850} is an apocalyptic number.

1978552117850 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1978552117850 is an abundant number, since it is smaller than the sum of its proper divisors (2800175211526).

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

1978552117850 is a wasteful number, since it uses less digits than its factorization.

1978552117850 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1707421 (or 1707409 counting only the distinct ones).

The product of its (nonzero) digits is 7056000, while the sum is 59.

The spelling of 1978552117850 in words is "one trillion, nine hundred seventy-eight billion, five hundred fifty-two million, one hundred seventeen thousand, eight hundred fifty".