21201402021 has 8 divisors (see below), whose sum is σ = 28277112864. Its totient is φ = 14129979600.

The previous prime is 21201402017. The next prime is 21201402031. The reversal of 21201402021 is 12020410212.

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

It is not a de Polignac number, because 21201402021 - 2² = 21201402017 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21201402011) 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, 1060551 + ... + 1080356.

It is an arithmetic number, because the mean of its divisors is an integer number (3534639108).

Almost surely, 2^21201402021 is an apocalyptic number.

It is an amenable number.

21201402021 is a deficient number, since it is larger than the sum of its proper divisors (7075710843).

21201402021 is a wasteful number, since it uses less digits than its factorization.

21201402021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2144211.

The product of its (nonzero) digits is 64, while the sum is 15.

Adding to 21201402021 its reverse (12020410212), we get a palindrome (33221812233).

The spelling of 21201402021 in words is "twenty-one billion, two hundred one million, four hundred two thousand, twenty-one".