1266639642 has 24 divisors (see below), whose sum is σ = 2762566560. Its totient is φ = 419416200.

The previous prime is 1266639631. The next prime is 1266639643. The reversal of 1266639642 is 2469366621.

It is not an unprimeable number, because it can be changed into a prime (1266639643) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 230292 + ... + 235727.

It is an arithmetic number, because the mean of its divisors is an integer number (115106940).

Almost surely, 2^1266639642 is an apocalyptic number.

1266639642 is an abundant number, since it is smaller than the sum of its proper divisors (1495926918).

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

1266639642 is a wasteful number, since it uses less digits than its factorization.

1266639642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 466178 (or 466175 counting only the distinct ones).

The product of its digits is 559872, while the sum is 45.

The square root of 1266639642 is about 35589.8811742889. The cubic root of 1266639642 is about 1081.9761606650.

The spelling of 1266639642 in words is "one billion, two hundred sixty-six million, six hundred thirty-nine thousand, six hundred forty-two".