21253150466 has 4 divisors (see below), whose sum is σ = 31879725702. Its totient is φ = 10626575232.

The previous prime is 21253150447. The next prime is 21253150489. The reversal of 21253150466 is 66405135212.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 17589390625 + 3663759841 = 132625^2 + 60529^2 .

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5313287615 + ... + 5313287618.

Almost surely, 2^21253150466 is an apocalyptic number.

21253150466 is a deficient number, since it is larger than the sum of its proper divisors (10626575236).

21253150466 is a wasteful number, since it uses less digits than its factorization.

21253150466 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10626575235.

The product of its (nonzero) digits is 43200, while the sum is 35.

Adding to 21253150466 its reverse (66405135212), we get a palindrome (87658285678).

The spelling of 21253150466 in words is "twenty-one billion, two hundred fifty-three million, one hundred fifty thousand, four hundred sixty-six".