159721399 has 2 divisors, whose sum is σ = 159721400. Its totient is φ = 159721398.

The previous prime is 159721381. The next prime is 159721469. The reversal of 159721399 is 993127951.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 159721399 - 2¹³ = 159713207 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (159721339) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 79860699 + 79860700.

It is an arithmetic number, because the mean of its divisors is an integer number (79860700).

Almost surely, 2^159721399 is an apocalyptic number.

159721399 is a deficient number, since it is larger than the sum of its proper divisors (1).

159721399 is an equidigital number, since it uses as much as digits as its factorization.

159721399 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 153090, while the sum is 46.

The square root of 159721399 is about 12638.0931710444. The cubic root of 159721399 is about 542.5682404760.

It can be divided in two parts, 15972 and 1399, that added together give a palindrome (17371).

The spelling of 159721399 in words is "one hundred fifty-nine million, seven hundred twenty-one thousand, three hundred ninety-nine".