1221403315 has 32 divisors (see below), whose sum is σ = 1698681600. Its totient is φ = 833742720.

The previous prime is 1221403307. The next prime is 1221403321. The reversal of 1221403315 is 5133041221.

It is a happy number.

It is not a de Polignac number, because 1221403315 - 2³ = 1221403307 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 108544 + ... + 119266.

It is an arithmetic number, because the mean of its divisors is an integer number (53083800).

Almost surely, 2^1221403315 is an apocalyptic number.

1221403315 is a deficient number, since it is larger than the sum of its proper divisors (477278285).

1221403315 is a wasteful number, since it uses less digits than its factorization.

1221403315 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10867.

The product of its (nonzero) digits is 720, while the sum is 22.

The square root of 1221403315 is about 34948.5810155434. The cubic root of 1221403315 is about 1068.9392681910.

Adding to 1221403315 its reverse (5133041221), we get a palindrome (6354444536).

It can be divided in two parts, 12 and 21403315, that multiplied together give a triangular number (256839780 = T₂₂₆₆₄).

The spelling of 1221403315 in words is "one billion, two hundred twenty-one million, four hundred three thousand, three hundred fifteen".