20905950 has 96 divisors (see below), whose sum is σ = 56996352. Its totient is φ = 5040000.

The previous prime is 20905949. The next prime is 20905967. The reversal of 20905950 is 5950902.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 138375 + ... + 138525.

It is an arithmetic number, because the mean of its divisors is an integer number (593712).

Almost surely, 2^20905950 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20905950, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28498176).

20905950 is an abundant number, since it is smaller than the sum of its proper divisors (36090402).

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

20905950 is a wasteful number, since it uses less digits than its factorization.

20905950 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 250 (or 245 counting only the distinct ones).

The product of its (nonzero) digits is 4050, while the sum is 30.

The square root of 20905950 is about 4572.3024834322. The cubic root of 20905950 is about 275.4799332773.

The spelling of 20905950 in words is "twenty million, nine hundred five thousand, nine hundred fifty".