1978204499826 has 16 divisors (see below), whose sum is σ = 4189138941024. Its totient is φ = 620613176384.

The previous prime is 1978204499807. The next prime is 1978204499891. The reversal of 1978204499826 is 6289944028791.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9697080780 + ... + 9697080983.

It is an arithmetic number, because the mean of its divisors is an integer number (261821183814).

Almost surely, 2^{1978204499826} is an apocalyptic number.

1978204499826 is an abundant number, since it is smaller than the sum of its proper divisors (2210934441198).

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

1978204499826 is a wasteful number, since it uses less digits than its factorization.

1978204499826 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19394161785.

The product of its (nonzero) digits is 125411328, while the sum is 69.

The spelling of 1978204499826 in words is "one trillion, nine hundred seventy-eight billion, two hundred four million, four hundred ninety-nine thousand, eight hundred twenty-six".