20999412 has 120 divisors (see below), whose sum is σ = 64399104. Its totient is φ = 5842368.

The previous prime is 20999401. The next prime is 20999423. The reversal of 20999412 is 21499902.

It is an interprime number because it is at equal distance from previous prime (20999401) and next prime (20999423).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 106498 + ... + 106694.

Almost surely, 2^20999412 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20999412, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32199552).

20999412 is an abundant number, since it is smaller than the sum of its proper divisors (43399692).

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

20999412 is a wasteful number, since it uses less digits than its factorization.

20999412 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 267 (or 256 counting only the distinct ones).

The product of its (nonzero) digits is 11664, while the sum is 36.

The square root of 20999412 is about 4582.5115384470. The cubic root of 20999412 is about 275.8898426182.

It can be divided in two parts, 2099 and 9412, that added together give a palindrome (11511).

The spelling of 20999412 in words is "twenty million, nine hundred ninety-nine thousand, four hundred twelve".