21523756004 has 6 divisors (see below), whose sum is σ = 37666573014. Its totient is φ = 10761878000.

The previous prime is 21523755893. The next prime is 21523756039. The reversal of 21523756004 is 40065732512.

It can be written as a sum of positive squares in only one way, i.e., 18958536100 + 2565219904 = 137690^2 + 50648^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2690469497 + ... + 2690469504.

It is an arithmetic number, because the mean of its divisors is an integer number (6277762169).

Almost surely, 2^21523756004 is an apocalyptic number.

It is an amenable number.

21523756004 is a deficient number, since it is larger than the sum of its proper divisors (16142817010).

21523756004 is a wasteful number, since it uses less digits than its factorization.

21523756004 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5380939005 (or 5380939003 counting only the distinct ones).

The product of its (nonzero) digits is 50400, while the sum is 35.

The spelling of 21523756004 in words is "twenty-one billion, five hundred twenty-three million, seven hundred fifty-six thousand, four".