20211428 has 12 divisors (see below), whose sum is σ = 35868672. Its totient is φ = 9963240.

The previous prime is 20211407. The next prime is 20211461. The reversal of 20211428 is 82411202.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 35300 + ... + 35867.

It is an arithmetic number, because the mean of its divisors is an integer number (2989056).

Almost surely, 2^20211428 is an apocalyptic number.

It is an amenable number.

20211428 is a deficient number, since it is larger than the sum of its proper divisors (15657244).

20211428 is a wasteful number, since it uses less digits than its factorization.

20211428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71242 (or 71240 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 20.

The square root of 20211428 is about 4495.7121793994. The cubic root of 20211428 is about 272.3949172584.

The spelling of 20211428 in words is "twenty million, two hundred eleven thousand, four hundred twenty-eight".