1215171151 has 4 divisors (see below), whose sum is σ = 1225924992. Its totient is φ = 1204417312.

The previous prime is 1215171109. The next prime is 1215171157. The reversal of 1215171151 is 1511715121.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1215171151 - 2⁹ = 1215170639 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1215171157) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5376751 + ... + 5376976.

It is an arithmetic number, because the mean of its divisors is an integer number (306481248).

Almost surely, 2^1215171151 is an apocalyptic number.

1215171151 is a deficient number, since it is larger than the sum of its proper divisors (10753841).

1215171151 is a wasteful number, since it uses less digits than its factorization.

1215171151 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10753840.

The product of its digits is 350, while the sum is 25.

The square root of 1215171151 is about 34859.3050848694. The cubic root of 1215171151 is about 1067.1180931794.

Adding to 1215171151 its reverse (1511715121), we get a palindrome (2726886272).

The spelling of 1215171151 in words is "one billion, two hundred fifteen million, one hundred seventy-one thousand, one hundred fifty-one".