1988831440 has 40 divisors (see below), whose sum is σ = 4666475880. Its totient is φ = 788230656.

The previous prime is 1988831423. The next prime is 1988831477. The reversal of 1988831440 is 441388891.

It can be written as a sum of positive squares in 4 ways, for example, as 8225424 + 1980606016 = 2868^2 + 44504^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 105319 + ... + 122758.

It is an arithmetic number, because the mean of its divisors is an integer number (116661897).

Almost surely, 2^1988831440 is an apocalyptic number.

1988831440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1988831440 is an abundant number, since it is smaller than the sum of its proper divisors (2677644440).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1988831440 is a wasteful number, since it uses less digits than its factorization.

1988831440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 228199 (or 228193 counting only the distinct ones).

The product of its (nonzero) digits is 221184, while the sum is 46.

The square root of 1988831440 is about 44596.3164398137. The cubic root of 1988831440 is about 1257.5714201485.

The spelling of 1988831440 in words is "one billion, nine hundred eighty-eight million, eight hundred thirty-one thousand, four hundred forty".