1215501240 has 64 divisors (see below), whose sum is σ = 3805056000. Its totient is φ = 310040192.

The previous prime is 1215501239. The next prime is 1215501247. The reversal of 1215501240 is 421055121.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1215501247) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 217440 + ... + 222959.

It is an arithmetic number, because the mean of its divisors is an integer number (59454000).

Almost surely, 2^1215501240 is an apocalyptic number.

1215501240 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1215501240 is an abundant number, since it is smaller than the sum of its proper divisors (2589554760).

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

1215501240 is a wasteful number, since it uses less digits than its factorization.

1215501240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 440436 (or 440432 counting only the distinct ones).

The product of its (nonzero) digits is 400, while the sum is 21.

The square root of 1215501240 is about 34864.0393528920. The cubic root of 1215501240 is about 1067.2147083913.

Adding to 1215501240 its reverse (421055121), we get a palindrome (1636556361).

The spelling of 1215501240 in words is "one billion, two hundred fifteen million, five hundred one thousand, two hundred forty".