19745852261 has 2 divisors, whose sum is σ = 19745852262. Its totient is φ = 19745852260.

The previous prime is 19745852221. The next prime is 19745852267. The reversal of 19745852261 is 16225854791.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17887725025 + 1858127236 = 133745^2 + 43106^2 .

It is a cyclic number.

It is not a de Polignac number, because 19745852261 - 2¹⁴ = 19745835877 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19745852267) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9872926130 + 9872926131.

It is an arithmetic number, because the mean of its divisors is an integer number (9872926131).

Almost surely, 2^19745852261 is an apocalyptic number.

It is an amenable number.

19745852261 is a deficient number, since it is larger than the sum of its proper divisors (1).

19745852261 is an equidigital number, since it uses as much as digits as its factorization.

19745852261 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1209600, while the sum is 50.

The spelling of 19745852261 in words is "nineteen billion, seven hundred forty-five million, eight hundred fifty-two thousand, two hundred sixty-one".