21530439867 has 8 divisors (see below), whose sum is σ = 28713991680. Its totient is φ = 14350257320.

The previous prime is 21530439851. The next prime is 21530439877. The reversal of 21530439867 is 76893403512.

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

It is a cyclic number.

It is not a de Polignac number, because 21530439867 - 2⁴ = 21530439851 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21530439877) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 827367 + ... + 852992.

It is an arithmetic number, because the mean of its divisors is an integer number (3589248960).

It is a 1-persistent number, because it is pandigital, but 2⋅21530439867 = 43060879734 is not.

Almost surely, 2^21530439867 is an apocalyptic number.

21530439867 is a deficient number, since it is larger than the sum of its proper divisors (7183551813).

21530439867 is a wasteful number, since it uses less digits than its factorization.

21530439867 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1684633.

The product of its (nonzero) digits is 1088640, while the sum is 48.

The spelling of 21530439867 in words is "twenty-one billion, five hundred thirty million, four hundred thirty-nine thousand, eight hundred sixty-seven".