1266844920 has 128 divisors (see below), whose sum is σ = 4203152640. Its totient is φ = 302883840.

The previous prime is 1266844907. The next prime is 1266844927. The reversal of 1266844920 is 294486621.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1266844927) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 89787 + ... + 102933.

It is an arithmetic number, because the mean of its divisors is an integer number (32837130).

Almost surely, 2^1266844920 is an apocalyptic number.

1266844920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1266844920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2101576320).

1266844920 is an abundant number, since it is smaller than the sum of its proper divisors (2936307720).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1266844920 is a wasteful number, since it uses less digits than its factorization.

1266844920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13245 (or 13241 counting only the distinct ones).

The product of its (nonzero) digits is 165888, while the sum is 42.

The square root of 1266844920 is about 35592.7649951503. The cubic root of 1266844920 is about 1082.0346076765.

The spelling of 1266844920 in words is "one billion, two hundred sixty-six million, eight hundred forty-four thousand, nine hundred twenty".