1221413651 has 8 divisors (see below), whose sum is σ = 1286931600. Its totient is φ = 1156019040.

The previous prime is 1221413629. The next prime is 1221413653. The reversal of 1221413651 is 1563141221.

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

It is a cyclic number.

It is not a de Polignac number, because 1221413651 - 2⁶ = 1221413587 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1221413651.

It is not an unprimeable number, because it can be changed into a prime (1221413653) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10136 + ... + 50453.

It is an arithmetic number, because the mean of its divisors is an integer number (160866450).

Almost surely, 2^1221413651 is an apocalyptic number.

1221413651 is a deficient number, since it is larger than the sum of its proper divisors (65517949).

1221413651 is a wasteful number, since it uses less digits than its factorization.

1221413651 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 61669.

The product of its digits is 1440, while the sum is 26.

The square root of 1221413651 is about 34948.7288896177. The cubic root of 1221413651 is about 1068.9422834454.

Adding to 1221413651 its reverse (1563141221), we get a palindrome (2784554872).

The spelling of 1221413651 in words is "one billion, two hundred twenty-one million, four hundred thirteen thousand, six hundred fifty-one".