1266116621 has 16 divisors (see below), whose sum is σ = 1602101760. Its totient is φ = 971855280.

The previous prime is 1266116587. The next prime is 1266116651.

1266116621 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 1266116621 - 2¹⁴ = 1266100237 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1266116651) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 117551 + ... + 127868.

It is an arithmetic number, because the mean of its divisors is an integer number (100131360).

Almost surely, 2^1266116621 is an apocalyptic number.

1266116621 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1266116621 is a deficient number, since it is larger than the sum of its proper divisors (335985139).

1266116621 is a wasteful number, since it uses less digits than its factorization.

1266116621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 245504.

The product of its digits is 5184, while the sum is 32.

The square root of 1266116621 is about 35582.5325265080. The cubic root of 1266116621 is about 1081.8272169185.

The spelling of 1266116621 in words is "one billion, two hundred sixty-six million, one hundred sixteen thousand, six hundred twenty-one".