21025759 has 2 divisors, whose sum is σ = 21025760. Its totient is φ = 21025758.

The previous prime is 21025751. The next prime is 21025793. The reversal of 21025759 is 95752012.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21025759 - 2³ = 21025751 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21025759.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21025751) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10512879 + 10512880.

It is an arithmetic number, because the mean of its divisors is an integer number (10512880).

Almost surely, 2^21025759 is an apocalyptic number.

21025759 is a deficient number, since it is larger than the sum of its proper divisors (1).

21025759 is an equidigital number, since it uses as much as digits as its factorization.

21025759 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6300, while the sum is 31.

The square root of 21025759 is about 4585.3853709367. The cubic root of 21025759 is about 276.0051765115.

The spelling of 21025759 in words is "twenty-one million, twenty-five thousand, seven hundred fifty-nine".