1987929897 has 4 divisors (see below), whose sum is σ = 2650573200. Its totient is φ = 1325286596.

The previous prime is 1987929887. The next prime is 1987929913. The reversal of 1987929897 is 7989297891.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1987929897 - 2¹² = 1987925801 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1987929877) 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 in 3 ways as a sum of consecutive naturals, for example, 331321647 + ... + 331321652.

It is an arithmetic number, because the mean of its divisors is an integer number (662643300).

Almost surely, 2^1987929897 is an apocalyptic number.

It is an amenable number.

1987929897 is a deficient number, since it is larger than the sum of its proper divisors (662643303).

1987929897 is an equidigital number, since it uses as much as digits as its factorization.

1987929897 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 662643302.

The product of its digits is 41150592, while the sum is 69.

The square root of 1987929897 is about 44586.2074749580. The cubic root of 1987929897 is about 1257.3813711843.

The spelling of 1987929897 in words is "one billion, nine hundred eighty-seven million, nine hundred twenty-nine thousand, eight hundred ninety-seven".