1988840631 has 4 divisors (see below), whose sum is σ = 2651787512. Its totient is φ = 1325893752.

The previous prime is 1988840603. The next prime is 1988840639. The reversal of 1988840631 is 1360488891.

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

It is not a de Polignac number, because 1988840631 - 2¹⁰ = 1988839607 is a prime.

It is a super-2 number, since 2×1988840631² = 7910974111032956322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1988840639) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 331473436 + ... + 331473441.

It is an arithmetic number, because the mean of its divisors is an integer number (662946878).

Almost surely, 2^1988840631 is an apocalyptic number.

1988840631 is a deficient number, since it is larger than the sum of its proper divisors (662946881).

1988840631 is an equidigital number, since it uses as much as digits as its factorization.

1988840631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 662946880.

The product of its (nonzero) digits is 331776, while the sum is 48.

The square root of 1988840631 is about 44596.4194863220. The cubic root of 1988840631 is about 1257.5733573533.

The spelling of 1988840631 in words is "one billion, nine hundred eighty-eight million, eight hundred forty thousand, six hundred thirty-one".