1215523011 has 16 divisors (see below), whose sum is σ = 1662021504. Its totient is φ = 789769344.

The previous prime is 1215522961. The next prime is 1215523039. The reversal of 1215523011 is 1103255121.

It is not a de Polignac number, because 1215523011 - 2⁶ = 1215522947 is a prime.

It is a super-2 number, since 2×1215523011² = 2954992380541012242, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1215523061) 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, 50155 + ... + 70331.

It is an arithmetic number, because the mean of its divisors is an integer number (103876344).

Almost surely, 2^1215523011 is an apocalyptic number.

1215523011 is a deficient number, since it is larger than the sum of its proper divisors (446498493).

1215523011 is a wasteful number, since it uses less digits than its factorization.

1215523011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20690.

The product of its (nonzero) digits is 300, while the sum is 21.

The square root of 1215523011 is about 34864.3515786541. The cubic root of 1215523011 is about 1067.2210800268.

Adding to 1215523011 its reverse (1103255121), we get a palindrome (2318778132).

The spelling of 1215523011 in words is "one billion, two hundred fifteen million, five hundred twenty-three thousand, eleven".