1266640 has 40 divisors (see below), whose sum is σ = 2999808. Its totient is φ = 497280.

The previous prime is 1266631. The next prime is 1266677. The reversal of 1266640 is 466621.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5569 + ... + 5791.

2^1266640 is an apocalyptic number.

1266640 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 1266640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1499904).

1266640 is an abundant number, since it is smaller than the sum of its proper divisors (1733168).

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

1266640 is a wasteful number, since it uses less digits than its factorization.

1266640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 307 (or 301 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 25.

The square root of 1266640 is about 1125.4510207024. The cubic root of 1266640 is about 108.1976262601.

The spelling of 1266640 in words is "one million, two hundred sixty-six thousand, six hundred forty".