21697048 has 8 divisors (see below), whose sum is σ = 40681980. Its totient is φ = 10848520.

The previous prime is 21697007. The next prime is 21697051. The reversal of 21697048 is 84079612.

It is a tau number, because it is divible by the number of its divisors (8).

It is a junction number, because it is equal to n+sod(n) for n = 21696998 and 21697016.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1356058 + ... + 1356073.

Almost surely, 2^21697048 is an apocalyptic number.

It is an amenable number.

21697048 is a deficient number, since it is larger than the sum of its proper divisors (18984932).

21697048 is a wasteful number, since it uses less digits than its factorization.

21697048 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2712137 (or 2712133 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 37.

The square root of 21697048 is about 4658.0090167367. The cubic root of 21697048 is about 278.9117966494.

The spelling of 21697048 in words is "twenty-one million, six hundred ninety-seven thousand, forty-eight".