20687842 has 8 divisors (see below), whose sum is σ = 35464896. Its totient is φ = 8866212.

The previous prime is 20687839. The next prime is 20687857. The reversal of 20687842 is 24878602.

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 738838 + ... + 738865.

It is an arithmetic number, because the mean of its divisors is an integer number (4433112).

Almost surely, 2^20687842 is an apocalyptic number.

20687842 is a deficient number, since it is larger than the sum of its proper divisors (14777054).

20687842 is a wasteful number, since it uses less digits than its factorization.

20687842 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1477712.

The product of its (nonzero) digits is 43008, while the sum is 37.

The square root of 20687842 is about 4548.3889455498. The cubic root of 20687842 is about 274.5185714534.

The spelling of 20687842 in words is "twenty million, six hundred eighty-seven thousand, eight hundred forty-two".