1221446651 has 6 divisors (see below), whose sum is σ = 1297523220. Its totient is φ = 1149596576.

The previous prime is 1221446609. The next prime is 1221446663. The reversal of 1221446651 is 1566441221.

It is a de Polignac number, because none of the positive numbers 2^k-1221446651 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1221446251) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2112941 + ... + 2113518.

It is an arithmetic number, because the mean of its divisors is an integer number (216253870).

Almost surely, 2^1221446651 is an apocalyptic number.

1221446651 is a deficient number, since it is larger than the sum of its proper divisors (76076569).

1221446651 is an equidigital number, since it uses as much as digits as its factorization.

1221446651 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4226493 (or 4226476 counting only the distinct ones).

The product of its digits is 11520, while the sum is 32.

The square root of 1221446651 is about 34949.2010066039. The cubic root of 1221446651 is about 1068.9519102080.

Adding to 1221446651 its reverse (1566441221), we get a palindrome (2787887872).

The spelling of 1221446651 in words is "one billion, two hundred twenty-one million, four hundred forty-six thousand, six hundred fifty-one".