21275787466 has 8 divisors (see below), whose sum is σ = 31943538180. Its totient is φ = 10627941408.

The previous prime is 21275787443. The next prime is 21275787473. The reversal of 21275787466 is 66478757212.

It can be written as a sum of positive squares in 2 ways, for example, as 19412570241 + 1863217225 = 139329^2 + 43165^2 .

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, 4973491 + ... + 4977766.

Almost surely, 2^21275787466 is an apocalyptic number.

21275787466 is a deficient number, since it is larger than the sum of its proper divisors (10667750714).

21275787466 is a wasteful number, since it uses less digits than its factorization.

21275787466 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9952328.

The product of its digits is 7902720, while the sum is 55.

The spelling of 21275787466 in words is "twenty-one billion, two hundred seventy-five million, seven hundred eighty-seven thousand, four hundred sixty-six".