20007220 has 24 divisors (see below), whose sum is σ = 42452424. Its totient is φ = 7919616.

The previous prime is 20007203. The next prime is 20007223. The reversal of 20007220 is 2270002.

It can be written as a sum of positive squares in 4 ways, for example, as 1240996 + 18766224 = 1114^2 + 4332^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 20007220.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20007223) 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, 3217 + ... + 7096.

It is an arithmetic number, because the mean of its divisors is an integer number (1768851).

Almost surely, 2^20007220 is an apocalyptic number.

20007220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20007220 is an abundant number, since it is smaller than the sum of its proper divisors (22445204).

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

20007220 is a wasteful number, since it uses less digits than its factorization.

20007220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10419 (or 10417 counting only the distinct ones).

The product of its (nonzero) digits is 56, while the sum is 13.

The square root of 20007220 is about 4472.9431027009. The cubic root of 20007220 is about 271.4744212218.

Adding to 20007220 its reverse (2270002), we get a palindrome (22277222).

It can be divided in two parts, 2000 and 7220, that multiplied together give a square (14440000 = 3800²).

The spelling of 20007220 in words is "twenty million, seven thousand, two hundred twenty".