157721814449 has 2 divisors, whose sum is σ = 157721814450. Its totient is φ = 157721814448.

The previous prime is 157721814389. The next prime is 157721814457. The reversal of 157721814449 is 944418127751.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 157597090225 + 124724224 = 396985^2 + 11168^2 .

It is a cyclic number.

It is not a de Polignac number, because 157721814449 - 2³² = 153426847153 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 157721814449.

It is not a weakly prime, because it can be changed into another prime (157721814469) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 78860907224 + 78860907225.

It is an arithmetic number, because the mean of its divisors is an integer number (78860907225).

Almost surely, 2^157721814449 is an apocalyptic number.

It is an amenable number.

157721814449 is a deficient number, since it is larger than the sum of its proper divisors (1).

157721814449 is an equidigital number, since it uses as much as digits as its factorization.

157721814449 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2257920, while the sum is 53.

The spelling of 157721814449 in words is "one hundred fifty-seven billion, seven hundred twenty-one million, eight hundred fourteen thousand, four hundred forty-nine".