21138077732 has 24 divisors (see below), whose sum is σ = 37286098080. Its totient is φ = 10484959680.

The previous prime is 21138077731. The next prime is 21138077743. The reversal of 21138077732 is 23777083112.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 21138077732.

It is not an unprimeable number, because it can be changed into a prime (21138077731) 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 7 ways as a sum of consecutive naturals, for example, 2609144 + ... + 2617232.

It is an arithmetic number, because the mean of its divisors is an integer number (1553587420).

Almost surely, 2^21138077732 is an apocalyptic number.

It is an amenable number.

21138077732 is a deficient number, since it is larger than the sum of its proper divisors (16148020348).

21138077732 is a wasteful number, since it uses less digits than its factorization.

21138077732 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13211 (or 13209 counting only the distinct ones).

The product of its (nonzero) digits is 98784, while the sum is 41.

The spelling of 21138077732 in words is "twenty-one billion, one hundred thirty-eight million, seventy-seven thousand, seven hundred thirty-two".