21471406690 has 8 divisors (see below), whose sum is σ = 38648532060. Its totient is φ = 8588562672.

The previous prime is 21471406667. The next prime is 21471406699. The reversal of 21471406690 is 9660417412.

It can be written as a sum of positive squares in 2 ways, for example, as 21086815369 + 384591321 = 145213^2 + 19611^2 .

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

It is a super-2 number, since 2×21471406690² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21471406699) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1073570325 + ... + 1073570344.

Almost surely, 2^21471406690 is an apocalyptic number.

21471406690 is a deficient number, since it is larger than the sum of its proper divisors (17177125370).

21471406690 is a wasteful number, since it uses less digits than its factorization.

21471406690 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2147140676.

The product of its (nonzero) digits is 72576, while the sum is 40.

The spelling of 21471406690 in words is "twenty-one billion, four hundred seventy-one million, four hundred six thousand, six hundred ninety".