20521992 has 64 divisors (see below), whose sum is σ = 54820800. Its totient is φ = 6379520.

The previous prime is 20521987. The next prime is 20522023. The reversal of 20521992 is 29912502.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 72892 + ... + 73172.

It is an arithmetic number, because the mean of its divisors is an integer number (856575).

Almost surely, 2^20521992 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 20521992, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27410400).

20521992 is an abundant number, since it is smaller than the sum of its proper divisors (34298808).

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

20521992 is a wasteful number, since it uses less digits than its factorization.

20521992 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 486 (or 482 counting only the distinct ones).

The product of its (nonzero) digits is 3240, while the sum is 30.

The square root of 20521992 is about 4530.1205281979. The cubic root of 20521992 is about 273.7830168054.

The spelling of 20521992 in words is "twenty million, five hundred twenty-one thousand, nine hundred ninety-two".