20494687 has 4 divisors (see below), whose sum is σ = 20523160. Its totient is φ = 20466216.

The previous prime is 20494667. The next prime is 20494699. The reversal of 20494687 is 78649402.

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

It is a cyclic number.

It is not a de Polignac number, because 20494687 - 2¹⁹ = 19970399 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20494667) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13128 + ... + 14605.

It is an arithmetic number, because the mean of its divisors is an integer number (5130790).

Almost surely, 2^20494687 is an apocalyptic number.

20494687 is a deficient number, since it is larger than the sum of its proper divisors (28473).

20494687 is an equidigital number, since it uses as much as digits as its factorization.

20494687 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28472.

The product of its (nonzero) digits is 96768, while the sum is 40.

The square root of 20494687 is about 4527.1058083504. The cubic root of 20494687 is about 273.6615379673.

The spelling of 20494687 in words is "twenty million, four hundred ninety-four thousand, six hundred eighty-seven".