21402205570 has 8 divisors (see below), whose sum is σ = 38523970044. Its totient is φ = 8560882224.

The previous prime is 21402205543. The next prime is 21402205589. The reversal of 21402205570 is 7550220412.

It can be written as a sum of positive squares in 2 ways, for example, as 20277475201 + 1124730369 = 142399^2 + 33537^2 .

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

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1070110269 + ... + 1070110288.

Almost surely, 2^21402205570 is an apocalyptic number.

21402205570 is a deficient number, since it is larger than the sum of its proper divisors (17121764474).

21402205570 is a wasteful number, since it uses less digits than its factorization.

21402205570 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2140220564.

The product of its (nonzero) digits is 5600, while the sum is 28.

Adding to 21402205570 its reverse (7550220412), we get a palindrome (28952425982).

The spelling of 21402205570 in words is "twenty-one billion, four hundred two million, two hundred five thousand, five hundred seventy".