1221277612 has 24 divisors (see below), whose sum is σ = 2207665152. Its totient is φ = 590542800.

The previous prime is 1221277597. The next prime is 1221277613. The reversal of 1221277612 is 2167721221.

It is a Harshad number since it is a multiple of its sum of digits (31).

It is not an unprimeable number, because it can be changed into a prime (1221277613) 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, 275937 + ... + 280327.

It is an arithmetic number, because the mean of its divisors is an integer number (91986048).

Almost surely, 2^1221277612 is an apocalyptic number.

It is an amenable number.

1221277612 is a deficient number, since it is larger than the sum of its proper divisors (986387540).

1221277612 is a wasteful number, since it uses less digits than its factorization.

1221277612 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6669 (or 6667 counting only the distinct ones).

The product of its digits is 4704, while the sum is 31.

The square root of 1221277612 is about 34946.7825700736. The cubic root of 1221277612 is about 1068.9025963068.

Adding to 1221277612 its reverse (2167721221), we get a palindrome (3388998833).

The spelling of 1221277612 in words is "one billion, two hundred twenty-one million, two hundred seventy-seven thousand, six hundred twelve".