21671464 has 16 divisors (see below), whose sum is σ = 43024500. Its totient is φ = 10198272.

The previous prime is 21671431. The next prime is 21671471. The reversal of 21671464 is 46417612.

It can be written as a sum of positive squares in 2 ways, for example, as 18922500 + 2748964 = 4350^2 + 1658^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 79539 + ... + 79810.

Almost surely, 2^21671464 is an apocalyptic number.

It is an amenable number.

21671464 is a deficient number, since it is larger than the sum of its proper divisors (21353036).

21671464 is a wasteful number, since it uses less digits than its factorization.

21671464 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 159372 (or 159368 counting only the distinct ones).

The product of its digits is 8064, while the sum is 31.

The square root of 21671464 is about 4655.2619689981. The cubic root of 21671464 is about 278.8021275689.

The spelling of 21671464 in words is "twenty-one million, six hundred seventy-one thousand, four hundred sixty-four".