1226201989 has 2 divisors, whose sum is σ = 1226201990. Its totient is φ = 1226201988.

The previous prime is 1226201957. The next prime is 1226202007. The reversal of 1226201989 is 9891026221.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 743652900 + 482549089 = 27270^2 + 21967^2 .

It is a cyclic number.

It is not a de Polignac number, because 1226201989 - 2⁵ = 1226201957 is a prime.

It is a super-2 number, since 2×1226201989² = 3007142635655112242, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1226201909) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 613100994 + 613100995.

It is an arithmetic number, because the mean of its divisors is an integer number (613100995).

Almost surely, 2^1226201989 is an apocalyptic number.

It is an amenable number.

1226201989 is a deficient number, since it is larger than the sum of its proper divisors (1).

1226201989 is an equidigital number, since it uses as much as digits as its factorization.

1226201989 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 31104, while the sum is 40.

The square root of 1226201989 is about 35017.1670613144. The cubic root of 1226201989 is about 1070.3373289350.

It can be divided in two parts, 122620 and 1989, that added together give a square (124609 = 353²).

The spelling of 1226201989 in words is "one billion, two hundred twenty-six million, two hundred one thousand, nine hundred eighty-nine".