21254377 has 2 divisors, whose sum is σ = 21254378. Its totient is φ = 21254376.

The previous prime is 21254371. The next prime is 21254381. The reversal of 21254377 is 77345212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16679056 + 4575321 = 4084^2 + 2139^2 .

It is a cyclic number.

It is not a de Polignac number, because 21254377 - 2⁷ = 21254249 is a prime.

It is not a weakly prime, because it can be changed into another prime (21254371) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10627188 + 10627189.

It is an arithmetic number, because the mean of its divisors is an integer number (10627189).

Almost surely, 2^21254377 is an apocalyptic number.

It is an amenable number.

21254377 is a deficient number, since it is larger than the sum of its proper divisors (1).

21254377 is an equidigital number, since it uses as much as digits as its factorization.

21254377 is an evil number, because the sum of its binary digits is even.

The product of its digits is 11760, while the sum is 31.

The square root of 21254377 is about 4610.2469565089. The cubic root of 21254377 is about 277.0019288531.

Adding to 21254377 its reverse (77345212), we get a palindrome (98599589).

The spelling of 21254377 in words is "twenty-one million, two hundred fifty-four thousand, three hundred seventy-seven".