1987767634 has 4 divisors (see below), whose sum is σ = 2981651454. Its totient is φ = 993883816.

The previous prime is 1987767629. The next prime is 1987767637. The reversal of 1987767634 is 4367677891.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 1277705025 + 710062609 = 35745^2 + 26647^2 .

It is a Smith number, since the sum of its digits (58) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (1987767637) by changing a digit.

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 as a sum of consecutive naturals, namely, 496941907 + ... + 496941910.

Almost surely, 2^1987767634 is an apocalyptic number.

1987767634 is a deficient number, since it is larger than the sum of its proper divisors (993883820).

1987767634 is an equidigital number, since it uses as much as digits as its factorization.

1987767634 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 993883819.

The product of its digits is 10668672, while the sum is 58.

The square root of 1987767634 is about 44584.3877831691. The cubic root of 1987767634 is about 1257.3471593768.

The spelling of 1987767634 in words is "one billion, nine hundred eighty-seven million, seven hundred sixty-seven thousand, six hundred thirty-four".