20156494 has 4 divisors (see below), whose sum is σ = 30234744. Its totient is φ = 10078246.

The previous prime is 20156489. The next prime is 20156501. The reversal of 20156494 is 49465102.

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

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5039122 + ... + 5039125.

It is an arithmetic number, because the mean of its divisors is an integer number (7558686).

Almost surely, 2^20156494 is an apocalyptic number.

20156494 is a deficient number, since it is larger than the sum of its proper divisors (10078250).

20156494 is a wasteful number, since it uses less digits than its factorization.

20156494 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10078249.

The product of its (nonzero) digits is 8640, while the sum is 31.

The square root of 20156494 is about 4489.5984230218. The cubic root of 20156494 is about 272.1479065099.

The spelling of 20156494 in words is "twenty million, one hundred fifty-six thousand, four hundred ninety-four".