408991988 has 24 divisors (see below), whose sum is σ = 747626880. Its totient is φ = 195521760.

The previous prime is 408991987. The next prime is 408991993. The reversal of 408991988 is 889199804.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (408991987) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5168 + ... + 29063.

It is an arithmetic number, because the mean of its divisors is an integer number (31151120).

Almost surely, 2^408991988 is an apocalyptic number.

It is an amenable number.

408991988 is a deficient number, since it is larger than the sum of its proper divisors (338634892).

408991988 is a wasteful number, since it uses less digits than its factorization.

408991988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34367 (or 34365 counting only the distinct ones).

The product of its (nonzero) digits is 1492992, while the sum is 56.

The square root of 408991988 is about 20223.5503312351. The cubic root of 408991988 is about 742.2865650366.

The spelling of 408991988 in words is "four hundred eight million, nine hundred ninety-one thousand, nine hundred eighty-eight".