21373040404 has 6 divisors (see below), whose sum is σ = 37402820714. Its totient is φ = 10686520200.

The previous prime is 21373040399. The next prime is 21373040449. The reversal of 21373040404 is 40404037312.

It can be written as a sum of positive squares in only one way, i.e., 21170832004 + 202208400 = 145502^2 + 14220^2 .

It is a super-2 number, since 2×21373040404² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2671630047 + ... + 2671630054.

Almost surely, 2^21373040404 is an apocalyptic number.

It is an amenable number.

21373040404 is a deficient number, since it is larger than the sum of its proper divisors (16029780310).

21373040404 is a wasteful number, since it uses less digits than its factorization.

21373040404 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5343260105 (or 5343260103 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 28.

Adding to 21373040404 its reverse (40404037312), we get a palindrome (61777077716).

The spelling of 21373040404 in words is "twenty-one billion, three hundred seventy-three million, forty thousand, four hundred four".