21797470 has 8 divisors (see below), whose sum is σ = 39235464. Its totient is φ = 8718984.

The previous prime is 21797467. The next prime is 21797507. The reversal of 21797470 is 7479712.

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1089864 + ... + 1089883.

It is an arithmetic number, because the mean of its divisors is an integer number (4904433).

Almost surely, 2^21797470 is an apocalyptic number.

21797470 is a deficient number, since it is larger than the sum of its proper divisors (17437994).

21797470 is a wasteful number, since it uses less digits than its factorization.

21797470 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2179754.

The product of its (nonzero) digits is 24696, while the sum is 37.

The square root of 21797470 is about 4668.7760708777. The cubic root of 21797470 is about 279.3414369608.

The spelling of 21797470 in words is "twenty-one million, seven hundred ninety-seven thousand, four hundred seventy".