20951888 has 20 divisors (see below), whose sum is σ = 42982740. Its totient is φ = 9859584.

The previous prime is 20951881. The next prime is 20951899. The reversal of 20951888 is 88815902.

It can be written as a sum of positive squares in 2 ways, for example, as 17372224 + 3579664 = 4168^2 + 1892^2 .

It is a super-2 number, since 2×20951888² = 877963221529088, which contains 22 as substring.

It is a Smith number, since the sum of its digits (41) coincides with the sum of the digits of its prime factors.

It is a plaindrome in base 13.

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 3 ways as a sum of consecutive naturals, for example, 38243 + ... + 38786.

It is an arithmetic number, because the mean of its divisors is an integer number (2149137).

Almost surely, 2^20951888 is an apocalyptic number.

It is an amenable number.

20951888 is an abundant number, since it is smaller than the sum of its proper divisors (22030852).

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

20951888 is a wasteful number, since it uses less digits than its factorization.

20951888 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77054 (or 77048 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 41.

The square root of 20951888 is about 4577.3232352544. The cubic root of 20951888 is about 275.6815623073.

The spelling of 20951888 in words is "twenty million, nine hundred fifty-one thousand, eight hundred eighty-eight".