15531252240 has 160 divisors (see below), whose sum is σ = 55779215616. Its totient is φ = 3501342720.

The previous prime is 15531252229. The next prime is 15531252281. The reversal of 15531252240 is 4225213551.

It is a super-2 number, since 2×15531252240² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 15531252198 and 15531252207.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 59320 + ... + 185960.

Almost surely, 2^15531252240 is an apocalyptic number.

15531252240 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 15531252240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27889607808).

15531252240 is an abundant number, since it is smaller than the sum of its proper divisors (40247963376).

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

15531252240 is a wasteful number, since it uses less digits than its factorization.

15531252240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 126737 (or 126731 counting only the distinct ones).

The product of its (nonzero) digits is 12000, while the sum is 30.

Adding to 15531252240 its reverse (4225213551), we get a palindrome (19756465791).

The spelling of 15531252240 in words is "fifteen billion, five hundred thirty-one million, two hundred fifty-two thousand, two hundred forty".