21267561783 has 32 divisors (see below), whose sum is σ = 32175682560. Its totient is φ = 12387185280.

The previous prime is 21267561739. The next prime is 21267561827. The reversal of 21267561783 is 38716576212.

It is an interprime number because it is at equal distance from previous prime (21267561739) and next prime (21267561827).

It is not a de Polignac number, because 21267561783 - 2⁶ = 21267561719 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21267561283) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 804313 + ... + 830333.

It is an arithmetic number, because the mean of its divisors is an integer number (1005490080).

Almost surely, 2^21267561783 is an apocalyptic number.

21267561783 is a deficient number, since it is larger than the sum of its proper divisors (10908120777).

21267561783 is a wasteful number, since it uses less digits than its factorization.

21267561783 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27159.

The product of its digits is 846720, while the sum is 48.

The spelling of 21267561783 in words is "twenty-one billion, two hundred sixty-seven million, five hundred sixty-one thousand, seven hundred eighty-three".