1987775798 has 16 divisors (see below), whose sum is σ = 3048721200. Its totient is φ = 971782656.

The previous prime is 1987775761. The next prime is 1987775807. The reversal of 1987775798 is 8975777891.

It is a super-2 number, since 2×1987775798² = 7902505246229073608, which contains 22 as substring.

It is a congruent number.

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, 45623 + ... + 77826.

It is an arithmetic number, because the mean of its divisors is an integer number (190545075).

Almost surely, 2^1987775798 is an apocalyptic number.

1987775798 is a deficient number, since it is larger than the sum of its proper divisors (1060945402).

1987775798 is a wasteful number, since it uses less digits than its factorization.

1987775798 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 123631.

The product of its digits is 62233920, while the sum is 68.

The square root of 1987775798 is about 44584.4793397882. The cubic root of 1987775798 is about 1257.3488807330.

The spelling of 1987775798 in words is "one billion, nine hundred eighty-seven million, seven hundred seventy-five thousand, seven hundred ninety-eight".