1242640764 has 36 divisors (see below), whose sum is σ = 3257460024. Its totient is φ = 414213264.

The previous prime is 1242640741. The next prime is 1242640781. The reversal of 1242640764 is 4670462421.

1242640764 is a `hidden beast` number, since 1 + 2 + 4 + 2 + 640 + 7 + 6 + 4 = 666.

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 638247 + ... + 640190.

Almost surely, 2^1242640764 is an apocalyptic number.

It is an amenable number.

1242640764 is an abundant number, since it is smaller than the sum of its proper divisors (2014819260).

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

1242640764 is a wasteful number, since it uses less digits than its factorization.

1242640764 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1278456 (or 1278442 counting only the distinct ones).

The product of its (nonzero) digits is 64512, while the sum is 36.

The square root of 1242640764 is about 35251.1101101795. The cubic root of 1242640764 is about 1075.0991836375.

The spelling of 1242640764 in words is "one billion, two hundred forty-two million, six hundred forty thousand, seven hundred sixty-four".