21160021406 has 8 divisors (see below), whose sum is σ = 31741681944. Its totient is φ = 10579460760.

The previous prime is 21160021391. The next prime is 21160021409. The reversal of 21160021406 is 60412006112.

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

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21160021409) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 225065 + ... + 304916.

It is an arithmetic number, because the mean of its divisors is an integer number (3967710243).

Almost surely, 2^21160021406 is an apocalyptic number.

21160021406 is a deficient number, since it is larger than the sum of its proper divisors (10581660538).

21160021406 is a wasteful number, since it uses less digits than its factorization.

21160021406 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 549946.

The product of its (nonzero) digits is 576, while the sum is 23.

Adding to 21160021406 its reverse (60412006112), we get a palindrome (81572027518).

The spelling of 21160021406 in words is "twenty-one billion, one hundred sixty million, twenty-one thousand, four hundred six".