1025720261 has 2 divisors, whose sum is σ = 1025720262. Its totient is φ = 1025720260.

The previous prime is 1025720239. The next prime is 1025720359. The reversal of 1025720261 is 1620275201.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 929091361 + 96628900 = 30481^2 + 9830^2 .

It is a cyclic number.

It is not a de Polignac number, because 1025720261 - 2¹⁸ = 1025458117 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1025720261.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1025720221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 512860130 + 512860131.

It is an arithmetic number, because the mean of its divisors is an integer number (512860131).

Almost surely, 2^1025720261 is an apocalyptic number.

It is an amenable number.

1025720261 is a deficient number, since it is larger than the sum of its proper divisors (1).

1025720261 is an equidigital number, since it uses as much as digits as its factorization.

1025720261 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1680, while the sum is 26.

The square root of 1025720261 is about 32026.8677987717. The cubic root of 1025720261 is about 1008.5009494154.

Adding to 1025720261 its reverse (1620275201), we get a palindrome (2645995462).

The spelling of 1025720261 in words is "one billion, twenty-five million, seven hundred twenty thousand, two hundred sixty-one".