21602797 has 4 divisors (see below), whose sum is σ = 21612096. Its totient is φ = 21593500.

The previous prime is 21602771. The next prime is 21602807. The reversal of 21602797 is 79720612.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 21602797 - 2¹⁹ = 21078509 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21602197) by changing a digit.

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, 2172 + ... + 6922.

It is an arithmetic number, because the mean of its divisors is an integer number (5403024).

Almost surely, 2^21602797 is an apocalyptic number.

It is an amenable number.

21602797 is a deficient number, since it is larger than the sum of its proper divisors (9299).

21602797 is an equidigital number, since it uses as much as digits as its factorization.

21602797 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9298.

The product of its (nonzero) digits is 10584, while the sum is 34.

The square root of 21602797 is about 4647.8809149977. The cubic root of 21602797 is about 278.5073503535.

The spelling of 21602797 in words is "twenty-one million, six hundred two thousand, seven hundred ninety-seven".