21193697 has 8 divisors (see below), whose sum is σ = 24331776. Its totient is φ = 18083232.

The previous prime is 21193691. The next prime is 21193727. The reversal of 21193697 is 79639112.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 21193697 - 2¹⁴ = 21177313 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21193697.

It is not an unprimeable number, because it can be changed into a prime (21193691) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5228 + ... + 8349.

It is an arithmetic number, because the mean of its divisors is an integer number (3041472).

Almost surely, 2^21193697 is an apocalyptic number.

It is an amenable number.

21193697 is a deficient number, since it is larger than the sum of its proper divisors (3138079).

21193697 is a wasteful number, since it uses less digits than its factorization.

21193697 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13807.

The product of its digits is 20412, while the sum is 38.

The square root of 21193697 is about 4603.6612603449. The cubic root of 21193697 is about 276.7380695047.

The spelling of 21193697 in words is "twenty-one million, one hundred ninety-three thousand, six hundred ninety-seven".