1978151591616 has 112 divisors (see below), whose sum is σ = 5537873404800. Its totient is φ = 621442547712.

The previous prime is 1978151591587. The next prime is 1978151591653. The reversal of 1978151591616 is 6161951518791.

It is a self number, because there is not a number n which added to its sum of digits gives 1978151591616.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 700746 + ... + 2108873.

Almost surely, 2^{1978151591616} is an apocalyptic number.

1978151591616 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

1978151591616 is an abundant number, since it is smaller than the sum of its proper divisors (3559721813184).

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

1978151591616 is a wasteful number, since it uses less digits than its factorization.

1978151591616 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2809846 (or 2809836 counting only the distinct ones).

The product of its digits is 4082400, while the sum is 60.

The spelling of 1978151591616 in words is "one trillion, nine hundred seventy-eight billion, one hundred fifty-one million, five hundred ninety-one thousand, six hundred sixteen".