20899428 has 24 divisors (see below), whose sum is σ = 53198880. Its totient is φ = 6333120.

The previous prime is 20899427. The next prime is 20899441. The reversal of 20899428 is 82499802.

It is a self number, because there is not a number n which added to its sum of digits gives 20899428.

It is not an unprimeable number, because it can be changed into a prime (20899423) 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, 79033 + ... + 79296.

It is an arithmetic number, because the mean of its divisors is an integer number (2216620).

Almost surely, 2^20899428 is an apocalyptic number.

It is an amenable number.

20899428 is an abundant number, since it is smaller than the sum of its proper divisors (32299452).

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

20899428 is a wasteful number, since it uses less digits than its factorization.

20899428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 158347 (or 158345 counting only the distinct ones).

The product of its (nonzero) digits is 82944, while the sum is 42.

The square root of 20899428 is about 4571.5892203915. The cubic root of 20899428 is about 275.4512832679.

The spelling of 20899428 in words is "twenty million, eight hundred ninety-nine thousand, four hundred twenty-eight".