20021455424 has 28 divisors (see below), whose sum is σ = 42067141164. Its totient is φ = 9421860864.

The previous prime is 20021455367. The next prime is 20021455427. The reversal of 20021455424 is 42455412002.

It can be written as a sum of positive squares in 2 ways, for example, as 18559157824 + 1462297600 = 136232^2 + 38240^2 .

It is not an unprimeable number, because it can be changed into a prime (20021455427) 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, 9199949 + ... + 9202124.

Almost surely, 2^20021455424 is an apocalyptic number.

It is an amenable number.

20021455424 is an abundant number, since it is smaller than the sum of its proper divisors (22045685740).

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

20021455424 is a wasteful number, since it uses less digits than its factorization.

20021455424 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18402102 (or 18402092 counting only the distinct ones).

The product of its (nonzero) digits is 12800, while the sum is 29.

Adding to 20021455424 its reverse (42455412002), we get a palindrome (62476867426).

The spelling of 20021455424 in words is "twenty billion, twenty-one million, four hundred fifty-five thousand, four hundred twenty-four".