20720992 has 12 divisors (see below), whose sum is σ = 40794516. Its totient is φ = 10360480.

The previous prime is 20720971. The next prime is 20721013. The reversal of 20720992 is 29902702.

It is an interprime number because it is at equal distance from previous prime (20720971) and next prime (20721013).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 323734 + ... + 323797.

It is an arithmetic number, because the mean of its divisors is an integer number (3399543).

Almost surely, 2^20720992 is an apocalyptic number.

It is an amenable number.

20720992 is a deficient number, since it is larger than the sum of its proper divisors (20073524).

20720992 is an equidigital number, since it uses as much as digits as its factorization.

20720992 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 647541 (or 647533 counting only the distinct ones).

The product of its (nonzero) digits is 4536, while the sum is 31.

The square root of 20720992 is about 4552.0316343365. The cubic root of 20720992 is about 274.6651218480.

It can be divided in two parts, 20720 and 992, that added together give a palindrome (21712).

The spelling of 20720992 in words is "twenty million, seven hundred twenty thousand, nine hundred ninety-two".