20238818 has 4 divisors (see below), whose sum is σ = 30358230. Its totient is φ = 10119408.

The previous prime is 20238809. The next prime is 20238821. The reversal of 20238818 is 81883202.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 81883202 = 2 ⋅40941601.

It can be written as a sum of positive squares in only one way, i.e., 16024009 + 4214809 = 4003^2 + 2053^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5059703 + ... + 5059706.

Almost surely, 2^20238818 is an apocalyptic number.

20238818 is a deficient number, since it is larger than the sum of its proper divisors (10119412).

20238818 is a wasteful number, since it uses less digits than its factorization.

20238818 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10119411.

The product of its (nonzero) digits is 6144, while the sum is 32.

The square root of 20238818 is about 4498.7573839895. The cubic root of 20238818 is about 272.5179092121.

The spelling of 20238818 in words is "twenty million, two hundred thirty-eight thousand, eight hundred eighteen".