1266417840 has 160 divisors (see below), whose sum is σ = 4049740800. Its totient is φ = 327178240.

The previous prime is 1266417829. The next prime is 1266417847. The reversal of 1266417840 is 487146621.

It is not an unprimeable number, because it can be changed into a prime (1266417847) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1761001 + ... + 1761719.

It is an arithmetic number, because the mean of its divisors is an integer number (25310880).

Almost surely, 2^1266417840 is an apocalyptic number.

1266417840 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 1266417840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2024870400).

1266417840 is an abundant number, since it is smaller than the sum of its proper divisors (2783322960).

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

1266417840 is a wasteful number, since it uses less digits than its factorization.

1266417840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 955 (or 949 counting only the distinct ones).

The product of its (nonzero) digits is 64512, while the sum is 39.

The square root of 1266417840 is about 35586.7649555281. The cubic root of 1266417840 is about 1081.9130018213.

The spelling of 1266417840 in words is "one billion, two hundred sixty-six million, four hundred seventeen thousand, eight hundred forty".