20639950 has 24 divisors (see below), whose sum is σ = 38513160. Its totient is φ = 8229600.

The previous prime is 20639939. The next prime is 20639959. The reversal of 20639950 is 5993602.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20639959) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 25045 + ... + 25855.

It is an arithmetic number, because the mean of its divisors is an integer number (1604715).

Almost surely, 2^20639950 is an apocalyptic number.

20639950 is a deficient number, since it is larger than the sum of its proper divisors (17873210).

20639950 is a wasteful number, since it uses less digits than its factorization.

20639950 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1332 (or 1327 counting only the distinct ones).

The product of its (nonzero) digits is 14580, while the sum is 34.

The square root of 20639950 is about 4543.1211738187. The cubic root of 20639950 is about 274.3065725137.

The spelling of 20639950 in words is "twenty million, six hundred thirty-nine thousand, nine hundred fifty".