1987211564 has 48 divisors (see below), whose sum is σ = 3806476800. Its totient is φ = 902249280.

The previous prime is 1987211543. The next prime is 1987211581. The reversal of 1987211564 is 4651127891.

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, 1168787 + ... + 1170485.

It is an arithmetic number, because the mean of its divisors is an integer number (79301600).

Almost surely, 2^1987211564 is an apocalyptic number.

It is an amenable number.

1987211564 is a deficient number, since it is larger than the sum of its proper divisors (1819265236).

1987211564 is a wasteful number, since it uses less digits than its factorization.

1987211564 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2070 (or 2068 counting only the distinct ones).

The product of its digits is 120960, while the sum is 44.

The square root of 1987211564 is about 44578.1511954006. The cubic root of 1987211564 is about 1257.2299025054.

The spelling of 1987211564 in words is "one billion, nine hundred eighty-seven million, two hundred eleven thousand, five hundred sixty-four".