1223664261 has 4 divisors (see below), whose sum is σ = 1631552352. Its totient is φ = 815776172.

The previous prime is 1223664257. The next prime is 1223664283. The reversal of 1223664261 is 1624663221.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1223664261 - 2² = 1223664257 is a prime.

It is a super-2 number, since 2×1223664261² = 2994708447297352242, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1223664241) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 203944041 + ... + 203944046.

It is an arithmetic number, because the mean of its divisors is an integer number (407888088).

Almost surely, 2^1223664261 is an apocalyptic number.

It is an amenable number.

1223664261 is a deficient number, since it is larger than the sum of its proper divisors (407888091).

1223664261 is an equidigital number, since it uses as much as digits as its factorization.

1223664261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 407888090.

The product of its digits is 20736, while the sum is 33.

The square root of 1223664261 is about 34980.9128097024. The cubic root of 1223664261 is about 1069.5984346339.

The spelling of 1223664261 in words is "one billion, two hundred twenty-three million, six hundred sixty-four thousand, two hundred sixty-one".