15501425220 has 60 divisors (see below), whose sum is σ = 48628550124. Its totient is φ = 4133712960.

The previous prime is 15501425189. The next prime is 15501425227. The reversal of 15501425220 is 2252410551.

15501425220 is a `hidden beast` number, since 1 + 550 + 1 + 42 + 52 + 20 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 9018921024 + 6482504196 = 94968^2 + 80514^2 .

It is a tau number, because it is divible by the number of its divisors (60).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (15501425227) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 4782771 + ... + 4786010.

Almost surely, 2^15501425220 is an apocalyptic number.

15501425220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

15501425220 is an abundant number, since it is smaller than the sum of its proper divisors (33127124904).

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

15501425220 is a wasteful number, since it uses less digits than its factorization.

15501425220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9568802 (or 9568791 counting only the distinct ones).

The product of its (nonzero) digits is 4000, while the sum is 27.

Adding to 15501425220 its reverse (2252410551), we get a palindrome (17753835771).

The spelling of 15501425220 in words is "fifteen billion, five hundred one million, four hundred twenty-five thousand, two hundred twenty".