21053177 has 4 divisors (see below), whose sum is σ = 21131136. Its totient is φ = 20975220.

The previous prime is 21053173. The next prime is 21053203. The reversal of 21053177 is 77135012.

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 21053177 - 2² = 21053173 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21053173) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 38573 + ... + 39114.

It is an arithmetic number, because the mean of its divisors is an integer number (5282784).

Almost surely, 2^21053177 is an apocalyptic number.

It is an amenable number.

21053177 is a deficient number, since it is larger than the sum of its proper divisors (77959).

21053177 is an equidigital number, since it uses as much as digits as its factorization.

21053177 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77958.

The product of its (nonzero) digits is 1470, while the sum is 26.

The square root of 21053177 is about 4588.3741129075. The cubic root of 21053177 is about 276.1250964458.

Adding to 21053177 its reverse (77135012), we get a palindrome (98188189).

The spelling of 21053177 in words is "twenty-one million, fifty-three thousand, one hundred seventy-seven".