21117464 has 16 divisors (see below), whose sum is σ = 39771600. Its totient is φ = 10511712.

The previous prime is 21117463. The next prime is 21117487. The reversal of 21117464 is 46471112.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21117463) 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, 3932 + ... + 7595.

It is an arithmetic number, because the mean of its divisors is an integer number (2485725).

Almost surely, 2^21117464 is an apocalyptic number.

It is an amenable number.

21117464 is a deficient number, since it is larger than the sum of its proper divisors (18654136).

21117464 is a wasteful number, since it uses less digits than its factorization.

21117464 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11762 (or 11758 counting only the distinct ones).

The product of its digits is 1344, while the sum is 26.

The square root of 21117464 is about 4595.3741958626. The cubic root of 21117464 is about 276.4058651002.

Adding to 21117464 its reverse (46471112), we get a palindrome (67588576).

The spelling of 21117464 in words is "twenty-one million, one hundred seventeen thousand, four hundred sixty-four".