157123261 has 2 divisors, whose sum is σ = 157123262. Its totient is φ = 157123260.

The previous prime is 157123249. The next prime is 157123277. The reversal of 157123261 is 162321751.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 144120025 + 13003236 = 12005^2 + 3606^2 .

It is an emirp because it is prime and its reverse (162321751) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-157123261 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (157123661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 78561630 + 78561631.

It is an arithmetic number, because the mean of its divisors is an integer number (78561631).

Almost surely, 2^157123261 is an apocalyptic number.

It is an amenable number.

157123261 is a deficient number, since it is larger than the sum of its proper divisors (1).

157123261 is an equidigital number, since it uses as much as digits as its factorization.

157123261 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2520, while the sum is 28.

The square root of 157123261 is about 12534.8817704835. The cubic root of 157123261 is about 539.6102136799.

The spelling of 157123261 in words is "one hundred fifty-seven million, one hundred twenty-three thousand, two hundred sixty-one".