20508842 has 4 divisors (see below), whose sum is σ = 30763266. Its totient is φ = 10254420.

The previous prime is 20508833. The next prime is 20508853. The reversal of 20508842 is 24880502.

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., 15531481 + 4977361 = 3941^2 + 2231^2 .

It is a super-2 number, since 2×20508842² = 841225200361928, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5127209 + ... + 5127212.

Almost surely, 2^20508842 is an apocalyptic number.

20508842 is a deficient number, since it is larger than the sum of its proper divisors (10254424).

20508842 is a wasteful number, since it uses less digits than its factorization.

20508842 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10254423.

The product of its (nonzero) digits is 5120, while the sum is 29.

The square root of 20508842 is about 4528.6688993566. The cubic root of 20508842 is about 273.7245264482.

The spelling of 20508842 in words is "twenty million, five hundred eight thousand, eight hundred forty-two".