20139998 has 4 divisors (see below), whose sum is σ = 30210000. Its totient is φ = 10069998.

The previous prime is 20139997. The next prime is 20140027. The reversal of 20139998 is 89993102.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20139991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5034998 + ... + 5035001.

It is an arithmetic number, because the mean of its divisors is an integer number (7552500).

Almost surely, 2^20139998 is an apocalyptic number.

20139998 is a deficient number, since it is larger than the sum of its proper divisors (10070002).

20139998 is a wasteful number, since it uses less digits than its factorization.

20139998 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10070001.

The product of its (nonzero) digits is 34992, while the sum is 41.

The square root of 20139998 is about 4487.7609116351. The cubic root of 20139998 is about 272.0736446349.

The spelling of 20139998 in words is "twenty million, one hundred thirty-nine thousand, nine hundred ninety-eight".