1215121431 has 16 divisors (see below), whose sum is σ = 1690875360. Its totient is φ = 775219200.

The previous prime is 1215121351. The next prime is 1215121463. The reversal of 1215121431 is 1341215121.

It is not a de Polignac number, because 1215121431 - 2¹⁵ = 1215088663 is a prime.

It is a super-2 number, since 2×1215121431² = 2953040184150975522, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1215121398 and 1215121407.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1215123431) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 51970 + ... + 71631.

It is an arithmetic number, because the mean of its divisors is an integer number (105679710).

Almost surely, 2^1215121431 is an apocalyptic number.

1215121431 is a deficient number, since it is larger than the sum of its proper divisors (475753929).

1215121431 is a wasteful number, since it uses less digits than its factorization.

1215121431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 123746.

The product of its digits is 240, while the sum is 21.

The square root of 1215121431 is about 34858.5919250907. The cubic root of 1215121431 is about 1067.1035388962.

Adding to 1215121431 its reverse (1341215121), we get a palindrome (2556336552).

The spelling of 1215121431 in words is "one billion, two hundred fifteen million, one hundred twenty-one thousand, four hundred thirty-one".