21003333401 has 16 divisors (see below), whose sum is σ = 21472704528. Its totient is φ = 20538316800.

The previous prime is 21003333397. The next prime is 21003333409. The reversal of 21003333401 is 10433330012.

It can be written as a sum of positive squares in 8 ways, for example, as 924160000 + 20079173401 = 30400^2 + 141701^2 .

It is a cyclic number.

It is not a de Polignac number, because 21003333401 - 2² = 21003333397 is a prime.

It is a super-2 number, since 2×21003333401² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21003333409) 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, 14656181 + ... + 14657613.

It is an arithmetic number, because the mean of its divisors is an integer number (1342044033).

Almost surely, 2^21003333401 is an apocalyptic number.

It is an amenable number.

21003333401 is a deficient number, since it is larger than the sum of its proper divisors (469371127).

21003333401 is a wasteful number, since it uses less digits than its factorization.

21003333401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2732.

The product of its (nonzero) digits is 648, while the sum is 20.

Adding to 21003333401 its reverse (10433330012), we get a palindrome (31436663413).

The spelling of 21003333401 in words is "twenty-one billion, three million, three hundred thirty-three thousand, four hundred one".