1215105172 has 24 divisors (see below), whose sum is σ = 2146237632. Its totient is φ = 601910400.

The previous prime is 1215105169. The next prime is 1215105173. The reversal of 1215105172 is 2715015121.

It is a super-2 number, since 2×1215105172² = 2952961158042299168, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1215105173) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 387772 + ... + 390892.

It is an arithmetic number, because the mean of its divisors is an integer number (89426568).

Almost surely, 2^1215105172 is an apocalyptic number.

It is an amenable number.

1215105172 is a deficient number, since it is larger than the sum of its proper divisors (931132460).

1215105172 is a wasteful number, since it uses less digits than its factorization.

1215105172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3999 (or 3997 counting only the distinct ones).

The product of its (nonzero) digits is 700, while the sum is 25.

The square root of 1215105172 is about 34858.3587106450. The cubic root of 1215105172 is about 1067.0987793955.

The spelling of 1215105172 in words is "one billion, two hundred fifteen million, one hundred five thousand, one hundred seventy-two".