20843138 has 4 divisors (see below), whose sum is σ = 31264710. Its totient is φ = 10421568.

The previous prime is 20843117. The next prime is 20843143. The reversal of 20843138 is 83134802.

It is a happy number.

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

It can be written as a sum of positive squares in only one way, i.e., 18292729 + 2550409 = 4277^2 + 1597^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 20843138.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5210783 + ... + 5210786.

Almost surely, 2^20843138 is an apocalyptic number.

20843138 is a deficient number, since it is larger than the sum of its proper divisors (10421572).

20843138 is a wasteful number, since it uses less digits than its factorization.

20843138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10421571.

The product of its (nonzero) digits is 4608, while the sum is 29.

The square root of 20843138 is about 4565.4285669584. The cubic root of 20843138 is about 275.2037630328.

The spelling of 20843138 in words is "twenty million, eight hundred forty-three thousand, one hundred thirty-eight".