25720001 has 2 divisors, whose sum is σ = 25720002. Its totient is φ = 25720000.

The previous prime is 25719983. The next prime is 25720007. The reversal of 25720001 is 10002752.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 23030401 + 2689600 = 4799^2 + 1640^2 .

It is a cyclic number.

It is not a de Polignac number, because 25720001 - 2⁶ = 25719937 is a prime.

It is a super-4 number, since 4×25720001⁴ (a number of 31 digits) contains 4444 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a plaindrome in base 11.

It is not a weakly prime, because it can be changed into another prime (25720007) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12860000 + 12860001.

It is an arithmetic number, because the mean of its divisors is an integer number (12860001).

Almost surely, 2^25720001 is an apocalyptic number.

It is an amenable number.

25720001 is a deficient number, since it is larger than the sum of its proper divisors (1).

25720001 is an equidigital number, since it uses as much as digits as its factorization.

25720001 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 140, while the sum is 17.

The square root of 25720001 is about 5071.4890318328. The cubic root of 25720001 is about 295.1823099847.

Adding to 25720001 its reverse (10002752), we get a palindrome (35722753).

The spelling of 25720001 in words is "twenty-five million, seven hundred twenty thousand, one".