721316146 has 4 divisors (see below), whose sum is σ = 1081974222. Its totient is φ = 360658072.

The previous prime is 721316143. The next prime is 721316149. The reversal of 721316146 is 641613127.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (721316143) and next prime (721316149).

It can be written as a sum of positive squares in only one way, i.e., 409617121 + 311699025 = 20239^2 + 17655^2 .

It is not an unprimeable number, because it can be changed into a prime (721316143) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 180329035 + ... + 180329038.

Almost surely, 2^721316146 is an apocalyptic number.

721316146 is a deficient number, since it is larger than the sum of its proper divisors (360658076).

721316146 is a wasteful number, since it uses less digits than its factorization.

721316146 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 360658075.

The product of its digits is 6048, while the sum is 31.

The square root of 721316146 is about 26857.3294651572. The cubic root of 721316146 is about 896.8267449277.

The spelling of 721316146 in words is "seven hundred twenty-one million, three hundred sixteen thousand, one hundred forty-six".