9891261451 has 2 divisors, whose sum is σ = 9891261452. Its totient is φ = 9891261450.

The previous prime is 9891261427. The next prime is 9891261461. The reversal of 9891261451 is 1541621989.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 9891261451 - 2¹⁹ = 9890737163 is a prime.

It is not a weakly prime, because it can be changed into another prime (9891261461) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4945630725 + 4945630726.

It is an arithmetic number, because the mean of its divisors is an integer number (4945630726).

Almost surely, 2^9891261451 is an apocalyptic number.

9891261451 is a deficient number, since it is larger than the sum of its proper divisors (1).

9891261451 is an equidigital number, since it uses as much as digits as its factorization.

9891261451 is an evil number, because the sum of its binary digits is even.

The product of its digits is 155520, while the sum is 46.

The square root of 9891261451 is about 99454.8211551356. The cubic root of 9891261451 is about 2146.5972097328.

The spelling of 9891261451 in words is "nine billion, eight hundred ninety-one million, two hundred sixty-one thousand, four hundred fifty-one".