661225151 has 2 divisors, whose sum is σ = 661225152. Its totient is φ = 661225150.

The previous prime is 661225111. The next prime is 661225153. The reversal of 661225151 is 151522166.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 661225151 - 2¹⁰ = 661224127 is a prime.

Together with 661225153, 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 (661225153) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 330612575 + 330612576.

It is an arithmetic number, because the mean of its divisors is an integer number (330612576).

Almost surely, 2^661225151 is an apocalyptic number.

661225151 is a deficient number, since it is larger than the sum of its proper divisors (1).

661225151 is an equidigital number, since it uses as much as digits as its factorization.

661225151 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3600, while the sum is 29.

The square root of 661225151 is about 25714.2985710285. The cubic root of 661225151 is about 871.1971676598.

The spelling of 661225151 in words is "six hundred sixty-one million, two hundred twenty-five thousand, one hundred fifty-one".