1223500891 has 4 divisors (see below), whose sum is σ = 1223585784. Its totient is φ = 1223416000.

The previous prime is 1223500853. The next prime is 1223500913. The reversal of 1223500891 is 1980053221.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 1223500891 - 2¹⁵ = 1223468123 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1223500391) 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, 14845 + ... + 51646.

It is an arithmetic number, because the mean of its divisors is an integer number (305896446).

Almost surely, 2^1223500891 is an apocalyptic number.

1223500891 is a deficient number, since it is larger than the sum of its proper divisors (84893).

1223500891 is an equidigital number, since it uses as much as digits as its factorization.

1223500891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 84892.

The product of its (nonzero) digits is 4320, while the sum is 31.

The square root of 1223500891 is about 34978.5776011547. The cubic root of 1223500891 is about 1069.5508322321.

The spelling of 1223500891 in words is "one billion, two hundred twenty-three million, five hundred thousand, eight hundred ninety-one".