21020221401 has 16 divisors (see below), whose sum is σ = 28710072000. Its totient is φ = 13675394048.

The previous prime is 21020221393. The next prime is 21020221457. The reversal of 21020221401 is 10412202012.

It is a cyclic number.

It is not a de Polignac number, because 21020221401 - 2³ = 21020221393 is a prime.

It is a super-3 number, since 3×21020221401³ (a number of 32 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (21020221471) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 409176 + ... + 457673.

It is an arithmetic number, because the mean of its divisors is an integer number (1794379500).

Almost surely, 2^21020221401 is an apocalyptic number.

It is an amenable number.

21020221401 is a deficient number, since it is larger than the sum of its proper divisors (7689850599).

21020221401 is a wasteful number, since it uses less digits than its factorization.

21020221401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 867048.

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

Adding to 21020221401 its reverse (10412202012), we get a palindrome (31432423413).

The spelling of 21020221401 in words is "twenty-one billion, twenty million, two hundred twenty-one thousand, four hundred one".