21234177767 has 4 divisors (see below), whose sum is σ = 23164557576. Its totient is φ = 19303797960.

The previous prime is 21234177749. The next prime is 21234177779. The reversal of 21234177767 is 76777143212.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21234177767 - 2⁸ = 21234177511 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21234177707) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 965189888 + ... + 965189909.

It is an arithmetic number, because the mean of its divisors is an integer number (5791139394).

Almost surely, 2^21234177767 is an apocalyptic number.

21234177767 is a deficient number, since it is larger than the sum of its proper divisors (1930379809).

21234177767 is a wasteful number, since it uses less digits than its factorization.

21234177767 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1930379808.

The product of its digits is 691488, while the sum is 47.

The spelling of 21234177767 in words is "twenty-one billion, two hundred thirty-four million, one hundred seventy-seven thousand, seven hundred sixty-seven".