1266403240 has 32 divisors (see below), whose sum is σ = 2850530760. Its totient is φ = 506361600.

The previous prime is 1266403217. The next prime is 1266403241. The reversal of 1266403240 is 423046621.

It can be written as a sum of positive squares in 4 ways, for example, as 1052483364 + 213919876 = 32442^2 + 14626^2 .

It is a junction number, because it is equal to n+sod(n) for n = 1266403199 and 1266403208.

It is not an unprimeable number, because it can be changed into a prime (1266403241) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 137170 + ... + 146110.

Almost surely, 2^1266403240 is an apocalyptic number.

1266403240 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1266403240 is an abundant number, since it is smaller than the sum of its proper divisors (1584127520).

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

1266403240 is a wasteful number, since it uses less digits than its factorization.

1266403240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12493 (or 12489 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 28.

The square root of 1266403240 is about 35586.5598224948. The cubic root of 1266403240 is about 1081.9088441649.

Adding to 1266403240 its reverse (423046621), we get a palindrome (1689449861).

The spelling of 1266403240 in words is "one billion, two hundred sixty-six million, four hundred three thousand, two hundred forty".