1221253132 has 12 divisors (see below), whose sum is σ = 2331483336. Its totient is φ = 555115040.

The previous prime is 1221253129. The next prime is 1221253151. The reversal of 1221253132 is 2313521221.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13877833 + ... + 13877920.

It is an arithmetic number, because the mean of its divisors is an integer number (194290278).

Almost surely, 2^1221253132 is an apocalyptic number.

It is an amenable number.

1221253132 is a deficient number, since it is larger than the sum of its proper divisors (1110230204).

1221253132 is a wasteful number, since it uses less digits than its factorization.

1221253132 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27755768 (or 27755766 counting only the distinct ones).

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

The square root of 1221253132 is about 34946.4323214831. The cubic root of 1221253132 is about 1068.8954543570.

Adding to 1221253132 its reverse (2313521221), we get a palindrome (3534774353).

The spelling of 1221253132 in words is "one billion, two hundred twenty-one million, two hundred fifty-three thousand, one hundred thirty-two".