1988469965 has 4 divisors (see below), whose sum is σ = 2386163964. Its totient is φ = 1590775968.

The previous prime is 1988469943. The next prime is 1988470039. The reversal of 1988469965 is 5699648891.

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

It can be written as a sum of positive squares in 2 ways, for example, as 1354387204 + 634082761 = 36802^2 + 25181^2 .

It is a cyclic number.

It is not a de Polignac number, because 1988469965 - 2¹⁸ = 1988207821 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 198846992 + ... + 198847001.

It is an arithmetic number, because the mean of its divisors is an integer number (596540991).

Almost surely, 2^1988469965 is an apocalyptic number.

It is an amenable number.

1988469965 is a deficient number, since it is larger than the sum of its proper divisors (397693999).

1988469965 is an equidigital number, since it uses as much as digits as its factorization.

1988469965 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 397693998.

The product of its digits is 33592320, while the sum is 65.

The square root of 1988469965 is about 44592.2635106136. The cubic root of 1988469965 is about 1257.4952266339.

The spelling of 1988469965 in words is "one billion, nine hundred eighty-eight million, four hundred sixty-nine thousand, nine hundred sixty-five".