20999994 has 8 divisors (see below), whose sum is σ = 42000000. Its totient is φ = 6999996.

The previous prime is 20999977. The next prime is 20999999. The reversal of 20999994 is 49999902.

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

20999994 is an admirable number.

It is not an unprimeable number, because it can be changed into a prime (20999999) 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, 1749994 + ... + 1750005.

It is an arithmetic number, because the mean of its divisors is an integer number (5250000).

Almost surely, 2^20999994 is an apocalyptic number.

20999994 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20999994 is a wasteful number, since it uses less digits than its factorization.

20999994 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3500004.

The product of its (nonzero) digits is 472392, while the sum is 51.

The square root of 20999994 is about 4582.5750403021. The cubic root of 20999994 is about 275.8923913626.

The spelling of 20999994 in words is "twenty million, nine hundred ninety-nine thousand, nine hundred ninety-four".