20071998 has 24 divisors (see below), whose sum is σ = 43571736. Its totient is φ = 6678000.

The previous prime is 20071991. The next prime is 20072027. The reversal of 20071998 is 89917002.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20071991) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 18388 + ... + 19448.

It is an arithmetic number, because the mean of its divisors is an integer number (1815489).

Almost surely, 2^20071998 is an apocalyptic number.

20071998 is an abundant number, since it is smaller than the sum of its proper divisors (23499738).

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

20071998 is a wasteful number, since it uses less digits than its factorization.

20071998 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2120 (or 2117 counting only the distinct ones).

The product of its (nonzero) digits is 9072, while the sum is 36.

The square root of 20071998 is about 4480.1783446644. The cubic root of 20071998 is about 271.7670926508.

It can be divided in two parts, 2007 and 1998, that added together give a triangular number (4005 = T₈₉).

The spelling of 20071998 in words is "twenty million, seventy-one thousand, nine hundred ninety-eight".