20725170 has 16 divisors (see below), whose sum is σ = 49740480. Its totient is φ = 5526704.

The previous prime is 20725153. The next prime is 20725171. The reversal of 20725170 is 7152702.

It is a self number, because there is not a number n which added to its sum of digits gives 20725170.

It is not an unprimeable number, because it can be changed into a prime (20725171) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 345390 + ... + 345449.

It is an arithmetic number, because the mean of its divisors is an integer number (3108780).

Almost surely, 2^20725170 is an apocalyptic number.

20725170 is an abundant number, since it is smaller than the sum of its proper divisors (29015310).

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

20725170 is a wasteful number, since it uses less digits than its factorization.

20725170 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 690849.

The product of its (nonzero) digits is 980, while the sum is 24.

The square root of 20725170 is about 4552.4905271730. The cubic root of 20725170 is about 274.6835809668.

Adding to 20725170 its reverse (7152702), we get a palindrome (27877872).

The spelling of 20725170 in words is "twenty million, seven hundred twenty-five thousand, one hundred seventy".