1221837264 has 40 divisors (see below), whose sum is σ = 3507126720. Its totient is φ = 407278944.

The previous prime is 1221837229. The next prime is 1221837329. The reversal of 1221837264 is 4627381221.

It is a happy number.

1221837264 is a `hidden beast` number, since 1 + 221 + 8 + 372 + 64 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 1413732 + ... + 1414595.

It is an arithmetic number, because the mean of its divisors is an integer number (87678168).

Almost surely, 2^1221837264 is an apocalyptic number.

It is an amenable number.

1221837264 is an abundant number, since it is smaller than the sum of its proper divisors (2285289456).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1221837264 is a wasteful number, since it uses less digits than its factorization.

1221837264 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2828344 (or 2828332 counting only the distinct ones).

The product of its digits is 32256, while the sum is 36.

The square root of 1221837264 is about 34954.7888564643. The cubic root of 1221837264 is about 1069.0658466920.

The spelling of 1221837264 in words is "one billion, two hundred twenty-one million, eight hundred thirty-seven thousand, two hundred sixty-four".