1264012638 has 16 divisors (see below), whose sum is σ = 2889171840. Its totient is φ = 361146456.

The previous prime is 1264012619. The next prime is 1264012643. The reversal of 1264012638 is 8362104621.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1264012599 and 1264012608.

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, 15047728 + ... + 15047811.

It is an arithmetic number, because the mean of its divisors is an integer number (180573240).

Almost surely, 2^1264012638 is an apocalyptic number.

1264012638 is an abundant number, since it is smaller than the sum of its proper divisors (1625159202).

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

1264012638 is a wasteful number, since it uses less digits than its factorization.

1264012638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30095551.

The product of its (nonzero) digits is 13824, while the sum is 33.

The square root of 1264012638 is about 35552.9554045792. The cubic root of 1264012638 is about 1081.2276386479.

The spelling of 1264012638 in words is "one billion, two hundred sixty-four million, twelve thousand, six hundred thirty-eight".