157821057787 has 2 divisors, whose sum is σ = 157821057788. Its totient is φ = 157821057786.

The previous prime is 157821057781. The next prime is 157821057803. The reversal of 157821057787 is 787750128751.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-157821057787 is a prime.

It is not a weakly prime, because it can be changed into another prime (157821057781) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 78910528893 + 78910528894.

It is an arithmetic number, because the mean of its divisors is an integer number (78910528894).

Almost surely, 2^157821057787 is an apocalyptic number.

157821057787 is a deficient number, since it is larger than the sum of its proper divisors (1).

157821057787 is an equidigital number, since it uses as much as digits as its factorization.

157821057787 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7683200, while the sum is 58.

The spelling of 157821057787 in words is "one hundred fifty-seven billion, eight hundred twenty-one million, fifty-seven thousand, seven hundred eighty-seven".