1264642563 has 16 divisors (see below), whose sum is σ = 1805444640. Its totient is φ = 784582656.

The previous prime is 1264642559. The next prime is 1264642579. The reversal of 1264642563 is 3652464621.

It is not a de Polignac number, because 1264642563 - 2² = 1264642559 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1264642543) 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 15 ways as a sum of consecutive naturals, for example, 134770 + ... + 143847.

It is an arithmetic number, because the mean of its divisors is an integer number (112840290).

Almost surely, 2^1264642563 is an apocalyptic number.

1264642563 is a deficient number, since it is larger than the sum of its proper divisors (540802077).

1264642563 is a wasteful number, since it uses less digits than its factorization.

1264642563 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 278726.

The product of its digits is 207360, while the sum is 39.

The square root of 1264642563 is about 35561.8132692921. The cubic root of 1264642563 is about 1081.4072199774.

The spelling of 1264642563 in words is "one billion, two hundred sixty-four million, six hundred forty-two thousand, five hundred sixty-three".