1987664635 has 16 divisors (see below), whose sum is σ = 2626359552. Its totient is φ = 1432060000.

The previous prime is 1987664617. The next prime is 1987664641. The reversal of 1987664635 is 5364667891.

It is not a de Polignac number, because 1987664635 - 2⁷ = 1987664507 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (55).

It is a Duffinian number.

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, 162991 + ... + 174760.

It is an arithmetic number, because the mean of its divisors is an integer number (164147472).

Almost surely, 2^1987664635 is an apocalyptic number.

1987664635 is a deficient number, since it is larger than the sum of its proper divisors (638694917).

1987664635 is a wasteful number, since it uses less digits than its factorization.

1987664635 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 337874.

The product of its digits is 6531840, while the sum is 55.

The square root of 1987664635 is about 44583.2326665530. The cubic root of 1987664635 is about 1257.3254419261.

It can be divided in two parts, 198766 and 4635, that added together give a square (203401 = 451²).

The spelling of 1987664635 in words is "one billion, nine hundred eighty-seven million, six hundred sixty-four thousand, six hundred thirty-five".