21138267722 has 32 divisors (see below), whose sum is σ = 37295475840. Its totient is φ = 8858531520.

The previous prime is 21138267713. The next prime is 21138267727. The reversal of 21138267722 is 22776283112.

It is a self number, because there is not a number n which added to its sum of digits gives 21138267722.

It is not an unprimeable number, because it can be changed into a prime (21138267727) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 195908 + ... + 284000.

It is an arithmetic number, because the mean of its divisors is an integer number (1165483620).

Almost surely, 2^21138267722 is an apocalyptic number.

21138267722 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

21138267722 is a deficient number, since it is larger than the sum of its proper divisors (16157208118).

21138267722 is a wasteful number, since it uses less digits than its factorization.

21138267722 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 88958.

The product of its digits is 112896, while the sum is 41.

The spelling of 21138267722 in words is "twenty-one billion, one hundred thirty-eight million, two hundred sixty-seven thousand, seven hundred twenty-two".