1221106637 has 2 divisors, whose sum is σ = 1221106638. Its totient is φ = 1221106636.

The previous prime is 1221106631. The next prime is 1221106643. The reversal of 1221106637 is 7366011221.

It is a balanced prime because it is at equal distance from previous prime (1221106631) and next prime (1221106643).

It can be written as a sum of positive squares in only one way, i.e., 831399556 + 389707081 = 28834^2 + 19741^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1221106637 is a prime.

It is a super-2 number, since 2×1221106637² = 2982202837850899538, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1221106631) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610553318 + 610553319.

It is an arithmetic number, because the mean of its divisors is an integer number (610553319).

Almost surely, 2^1221106637 is an apocalyptic number.

It is an amenable number.

1221106637 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221106637 is an equidigital number, since it uses as much as digits as its factorization.

1221106637 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3024, while the sum is 29.

The square root of 1221106637 is about 34944.3362649801. The cubic root of 1221106637 is about 1068.8527129856.

Adding to 1221106637 its reverse (7366011221), we get a palindrome (8587117858).

The spelling of 1221106637 in words is "one billion, two hundred twenty-one million, one hundred six thousand, six hundred thirty-seven".