1987211265 has 16 divisors (see below), whose sum is σ = 3424118208. Its totient is φ = 978319296.

The previous prime is 1987211257. The next prime is 1987211327. The reversal of 1987211265 is 5621127891.

It is not a de Polignac number, because 1987211265 - 2³ = 1987211257 is a prime.

It is a super-2 number, since 2×1987211265² = 7898017223485800450, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5095219 + ... + 5095608.

It is an arithmetic number, because the mean of its divisors is an integer number (214007388).

Almost surely, 2^1987211265 is an apocalyptic number.

1987211265 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1987211265 is a deficient number, since it is larger than the sum of its proper divisors (1436906943).

1987211265 is a wasteful number, since it uses less digits than its factorization.

1987211265 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10190848.

The product of its digits is 60480, while the sum is 42.

The square root of 1987211265 is about 44578.1478417397. The cubic root of 1987211265 is about 1257.2298394502.

The spelling of 1987211265 in words is "one billion, nine hundred eighty-seven million, two hundred eleven thousand, two hundred sixty-five".