20639794 has 8 divisors (see below), whose sum is σ = 35382528. Its totient is φ = 8845620.

The previous prime is 20639791. The next prime is 20639803. The reversal of 20639794 is 49793602.

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

It is not an unprimeable number, because it can be changed into a prime (20639791) 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, 737122 + ... + 737149.

It is an arithmetic number, because the mean of its divisors is an integer number (4422816).

Almost surely, 2^20639794 is an apocalyptic number.

20639794 is a deficient number, since it is larger than the sum of its proper divisors (14742734).

20639794 is a wasteful number, since it uses less digits than its factorization.

20639794 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1474280.

The product of its (nonzero) digits is 81648, while the sum is 40.

The square root of 20639794 is about 4543.1040049728. The cubic root of 20639794 is about 274.3058814278.

It can be divided in two parts, 206 and 39794, that added together give a square (40000 = 200²).

The spelling of 20639794 in words is "twenty million, six hundred thirty-nine thousand, seven hundred ninety-four".