20397672 has 48 divisors (see below), whose sum is σ = 57154500. Its totient is φ = 6564096.

The previous prime is 20397647. The next prime is 20397673. The reversal of 20397672 is 27679302.

It can be written as a sum of positive squares in 2 ways, for example, as 20304036 + 93636 = 4506^2 + 306^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (20397673) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2797 + ... + 6972.

Almost surely, 2^20397672 is an apocalyptic number.

It is an amenable number.

20397672 is an abundant number, since it is smaller than the sum of its proper divisors (36756828).

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

20397672 is a wasteful number, since it uses less digits than its factorization.

20397672 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9810 (or 9803 counting only the distinct ones).

The product of its (nonzero) digits is 31752, while the sum is 36.

The square root of 20397672 is about 4516.3781949699. The cubic root of 20397672 is about 273.2290474000.

The spelling of 20397672 in words is "twenty million, three hundred ninety-seven thousand, six hundred seventy-two".