21032377 has 4 divisors (see below), whose sum is σ = 21186036. Its totient is φ = 20878720.

The previous prime is 21032371. The next prime is 21032387. The reversal of 21032377 is 77323012.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 11723776 + 9308601 = 3424^2 + 3051^2 .

It is a cyclic number.

It is not a de Polignac number, because 21032377 - 2¹¹ = 21030329 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21032371) 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, 76624 + ... + 76897.

It is an arithmetic number, because the mean of its divisors is an integer number (5296509).

Almost surely, 2^21032377 is an apocalyptic number.

It is an amenable number.

21032377 is a deficient number, since it is larger than the sum of its proper divisors (153659).

21032377 is a wasteful number, since it uses less digits than its factorization.

21032377 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 153658.

The product of its (nonzero) digits is 1764, while the sum is 25.

The square root of 21032377 is about 4586.1069547057. The cubic root of 21032377 is about 276.0341316397.

Adding to 21032377 its reverse (77323012), we get a palindrome (98355389).

The spelling of 21032377 in words is "twenty-one million, thirty-two thousand, three hundred seventy-seven".