21303077 has 4 divisors (see below), whose sum is σ = 21312576. Its totient is φ = 21293580.

The previous prime is 21303059. The next prime is 21303109. The reversal of 21303077 is 77030312.

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 21303077 - 2¹⁴ = 21286693 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 (21303577) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 698 + ... + 6564.

It is an arithmetic number, because the mean of its divisors is an integer number (5328144).

Almost surely, 2^21303077 is an apocalyptic number.

It is an amenable number.

21303077 is a deficient number, since it is larger than the sum of its proper divisors (9499).

21303077 is an equidigital number, since it uses as much as digits as its factorization.

21303077 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9498.

The product of its (nonzero) digits is 882, while the sum is 23.

The square root of 21303077 is about 4615.5256472042. The cubic root of 21303077 is about 277.2133316441.

Adding to 21303077 its reverse (77030312), we get a palindrome (98333389).

It can be divided in two parts, 2130 and 3077, that multiplied together give a triangular number (6554010 = T₃₆₂₀).

The spelling of 21303077 in words is "twenty-one million, three hundred three thousand, seventy-seven".