1221216502 has 8 divisors (see below), whose sum is σ = 1998354312. Its totient is φ = 555098400.

The previous prime is 1221216497. The next prime is 1221216527. The reversal of 1221216502 is 2056121221.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Harshad number since it is a multiple of its sum of digits (22), and also a Moran number because the ratio is a prime number: 55509841 = 1221216502 / (1 + 2 + 2 + 1 + 2 + 1 + 6 + 5 + 0 + 2).

It is a congruent number.

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, 27754899 + ... + 27754942.

It is an arithmetic number, because the mean of its divisors is an integer number (249794289).

Almost surely, 2^1221216502 is an apocalyptic number.

1221216502 is a deficient number, since it is larger than the sum of its proper divisors (777137810).

1221216502 is a wasteful number, since it uses less digits than its factorization.

1221216502 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55509854.

The product of its (nonzero) digits is 480, while the sum is 22.

The square root of 1221216502 is about 34945.9082297198. The cubic root of 1221216502 is about 1068.8847675111.

Adding to 1221216502 its reverse (2056121221), we get a palindrome (3277337723).

The spelling of 1221216502 in words is "one billion, two hundred twenty-one million, two hundred sixteen thousand, five hundred two".