21525221607 has 8 divisors (see below), whose sum is σ = 29367744384. Its totient is φ = 14016423288.

The previous prime is 21525221567. The next prime is 21525221651. The reversal of 21525221607 is 70612252512.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21525221607 - 2⁷ = 21525221479 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21525321607) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 83430963 + ... + 83431220.

It is an arithmetic number, because the mean of its divisors is an integer number (3670968048).

Almost surely, 2^21525221607 is an apocalyptic number.

21525221607 is a deficient number, since it is larger than the sum of its proper divisors (7842522777).

21525221607 is a wasteful number, since it uses less digits than its factorization.

21525221607 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 166862229.

The product of its (nonzero) digits is 16800, while the sum is 33.

The spelling of 21525221607 in words is "twenty-one billion, five hundred twenty-five million, two hundred twenty-one thousand, six hundred seven".