20955900 has 144 divisors (see below), whose sum is σ = 73495296. Its totient is φ = 4500480.

The previous prime is 20955899. The next prime is 20955911. The reversal of 20955900 is 955902.

20955900 = T₂₅ + T₂₆ + ... + T₅₀₀.

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, 35407 + ... + 35993.

It is an arithmetic number, because the mean of its divisors is an integer number (510384).

Almost surely, 2^20955900 is an apocalyptic number.

20955900 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20955900, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36747648).

20955900 is an abundant number, since it is smaller than the sum of its proper divisors (52539396).

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

20955900 is a wasteful number, since it uses less digits than its factorization.

20955900 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 628 (or 621 counting only the distinct ones).

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

The square root of 20955900 is about 4577.7614616753. The cubic root of 20955900 is about 275.6991576005.

The spelling of 20955900 in words is "twenty million, nine hundred fifty-five thousand, nine hundred".