15205401220 has 24 divisors (see below), whose sum is σ = 33032424600. Its totient is φ = 5872430592.

The previous prime is 15205401209. The next prime is 15205401247. The reversal of 15205401220 is 2210450251.

It can be written as a sum of positive squares in 4 ways, for example, as 1002482244 + 14202918976 = 31662^2 + 119176^2 .

It is a super-2 number, since 2×15205401220² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 15205401191 and 15205401200.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13107525 + ... + 13108684.

It is an arithmetic number, because the mean of its divisors is an integer number (1376351025).

Almost surely, 2^15205401220 is an apocalyptic number.

15205401220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

15205401220 is an abundant number, since it is smaller than the sum of its proper divisors (17827023380).

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

15205401220 is a wasteful number, since it uses less digits than its factorization.

15205401220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26216247 (or 26216245 counting only the distinct ones).

The product of its (nonzero) digits is 800, while the sum is 22.

Adding to 15205401220 its reverse (2210450251), we get a palindrome (17415851471).

The spelling of 15205401220 in words is "fifteen billion, two hundred five million, four hundred one thousand, two hundred twenty".