20951885 has 8 divisors (see below), whose sum is σ = 25173240. Its totient is φ = 16740864.

The previous prime is 20951881. The next prime is 20951899. The reversal of 20951885 is 58815902.

It can be written as a sum of positive squares in 4 ways, for example, as 276676 + 20675209 = 526^2 + 4547^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 20951885 - 2² = 20951881 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20951881) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2969 + ... + 7121.

It is an arithmetic number, because the mean of its divisors is an integer number (3146655).

Almost surely, 2^20951885 is an apocalyptic number.

It is an amenable number.

20951885 is a deficient number, since it is larger than the sum of its proper divisors (4221355).

20951885 is a wasteful number, since it uses less digits than its factorization.

20951885 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5167.

The product of its (nonzero) digits is 28800, while the sum is 38.

The square root of 20951885 is about 4577.3229075520. The cubic root of 20951885 is about 275.6815491495.

The spelling of 20951885 in words is "twenty million, nine hundred fifty-one thousand, eight hundred eighty-five".