20021456 has 40 divisors (see below), whose sum is σ = 47746944. Its totient is φ = 7920000.

The previous prime is 20021429. The next prime is 20021467. The reversal of 20021456 is 65412002.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5420 + ... + 8331.

Almost surely, 2^20021456 is an apocalyptic number.

20021456 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

20021456 is an abundant number, since it is smaller than the sum of its proper divisors (27725488).

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

20021456 is a wasteful number, since it uses less digits than its factorization.

20021456 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13779 (or 13773 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 20.

The square root of 20021456 is about 4474.5341656981. The cubic root of 20021456 is about 271.5387945428.

Adding to 20021456 its reverse (65412002), we get a palindrome (85433458).

The spelling of 20021456 in words is "twenty million, twenty-one thousand, four hundred fifty-six".