21254725357 has 2 divisors, whose sum is σ = 21254725358. Its totient is φ = 21254725356.

The previous prime is 21254725319. The next prime is 21254725367. The reversal of 21254725357 is 75352745212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16125444196 + 5129281161 = 126986^2 + 71619^2 .

It is a cyclic number.

It is not a de Polignac number, because 21254725357 - 2⁷ = 21254725229 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21254725367) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10627362678 + 10627362679.

It is an arithmetic number, because the mean of its divisors is an integer number (10627362679).

Almost surely, 2^21254725357 is an apocalyptic number.

It is an amenable number.

21254725357 is a deficient number, since it is larger than the sum of its proper divisors (1).

21254725357 is an equidigital number, since it uses as much as digits as its factorization.

21254725357 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 588000, while the sum is 43.

The spelling of 21254725357 in words is "twenty-one billion, two hundred fifty-four million, seven hundred twenty-five thousand, three hundred fifty-seven".