151691261 has 2 divisors, whose sum is σ = 151691262. Its totient is φ = 151691260.

The previous prime is 151691251. The next prime is 151691263. The reversal of 151691261 is 162196151.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 126990361 + 24700900 = 11269^2 + 4970^2 .

It is a cyclic number.

It is not a de Polignac number, because 151691261 - 2¹⁰ = 151690237 is a prime.

Together with 151691263, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (151691263) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 75845630 + 75845631.

It is an arithmetic number, because the mean of its divisors is an integer number (75845631).

Almost surely, 2^151691261 is an apocalyptic number.

It is an amenable number.

151691261 is a deficient number, since it is larger than the sum of its proper divisors (1).

151691261 is an equidigital number, since it uses as much as digits as its factorization.

151691261 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3240, while the sum is 32.

The square root of 151691261 is about 12316.3006215340. The cubic root of 151691261 is about 533.3187516413.

The spelling of 151691261 in words is "one hundred fifty-one million, six hundred ninety-one thousand, two hundred sixty-one".