21042534767 has 2 divisors, whose sum is σ = 21042534768. Its totient is φ = 21042534766.

The previous prime is 21042534727. The next prime is 21042534797. The reversal of 21042534767 is 76743524012.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21042534767 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21042534727) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10521267383 + 10521267384.

It is an arithmetic number, because the mean of its divisors is an integer number (10521267384).

Almost surely, 2^21042534767 is an apocalyptic number.

21042534767 is a deficient number, since it is larger than the sum of its proper divisors (1).

21042534767 is an equidigital number, since it uses as much as digits as its factorization.

21042534767 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 282240, while the sum is 41.

The spelling of 21042534767 in words is "twenty-one billion, forty-two million, five hundred thirty-four thousand, seven hundred sixty-seven".