1988621998 has 32 divisors (see below), whose sum is σ = 3402051840. Its totient is φ = 862973760.

The previous prime is 1988621951. The next prime is 1988622019. The reversal of 1988621998 is 8991268891.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 284461 + ... + 291367.

It is an arithmetic number, because the mean of its divisors is an integer number (106314120).

Almost surely, 2^1988621998 is an apocalyptic number.

1988621998 is a deficient number, since it is larger than the sum of its proper divisors (1413429842).

1988621998 is a wasteful number, since it uses less digits than its factorization.

1988621998 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7512.

The product of its digits is 4478976, while the sum is 61.

The square root of 1988621998 is about 44593.9681795644. The cubic root of 1988621998 is about 1257.5272740377.

The spelling of 1988621998 in words is "one billion, nine hundred eighty-eight million, six hundred twenty-one thousand, nine hundred ninety-eight".