15222240 has 216 divisors, whose sum is σ = 58555224. Its totient is φ = 3571200.

The previous prime is 15222239. The next prime is 15222247. The reversal of 15222240 is 4222251.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15222247) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 491025 + ... + 491055.

It is an arithmetic number, because the mean of its divisors is an integer number (271089).

Almost surely, 2^15222240 is an apocalyptic number.

15222240 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 15222240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29277612).

15222240 is an abundant number, since it is smaller than the sum of its proper divisors (43332984).

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

15222240 is a wasteful number, since it uses less digits than its factorization.

15222240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 94 (or 52 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 18.

The square root of 15222240 is about 3901.5689151930. The cubic root of 15222240 is about 247.8332212005.

Adding to 15222240 its reverse (4222251), we get a palindrome (19444491).

The spelling of 15222240 in words is "fifteen million, two hundred twenty-two thousand, two hundred forty".