20731672 has 16 divisors (see below), whose sum is σ = 41862240. Its totient is φ = 9568416.

The previous prime is 20731663. The next prime is 20731681. The reversal of 20731672 is 27613702.

It is an interprime number because it is at equal distance from previous prime (20731663) and next prime (20731681).

It is a self number, because there is not a number n which added to its sum of digits gives 20731672.

It is a congruent 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, 99568 + ... + 99775.

It is an arithmetic number, because the mean of its divisors is an integer number (2616390).

Almost surely, 2^20731672 is an apocalyptic number.

It is an amenable number.

20731672 is an abundant number, since it is smaller than the sum of its proper divisors (21130568).

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

20731672 is a wasteful number, since it uses less digits than its factorization.

20731672 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 199362 (or 199358 counting only the distinct ones).

The product of its (nonzero) digits is 3528, while the sum is 28.

The square root of 20731672 is about 4553.2045857835. The cubic root of 20731672 is about 274.7123029814.

The spelling of 20731672 in words is "twenty million, seven hundred thirty-one thousand, six hundred seventy-two".