21026077 has 4 divisors (see below), whose sum is σ = 21103936. Its totient is φ = 20948220.

The previous prime is 21026069. The next prime is 21026081. The reversal of 21026077 is 77062012.

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.

It is a cyclic number.

It is not a de Polignac number, because 21026077 - 2³ = 21026069 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 (21026377) 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, 38523 + ... + 39064.

It is an arithmetic number, because the mean of its divisors is an integer number (5275984).

Almost surely, 2^21026077 is an apocalyptic number.

It is an amenable number.

21026077 is a deficient number, since it is larger than the sum of its proper divisors (77859).

21026077 is an equidigital number, since it uses as much as digits as its factorization.

21026077 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77858.

The product of its (nonzero) digits is 1176, while the sum is 25.

The square root of 21026077 is about 4585.4200461899. The cubic root of 21026077 is about 276.0065679666.

Adding to 21026077 its reverse (77062012), we get a palindrome (98088089).

The spelling of 21026077 in words is "twenty-one million, twenty-six thousand, seventy-seven".