1000394721 has 6 divisors (see below), whose sum is σ = 1445014610. Its totient is φ = 666929808.

The previous prime is 1000394719. The next prime is 1000394723. The reversal of 1000394721 is 1274930001.

It is an interprime number because it is at equal distance from previous prime (1000394719) and next prime (1000394723).

It can be written as a sum of positive squares in only one way, i.e., 867891600 + 132503121 = 29460^2 + 11511^2 .

It is not a de Polignac number, because 1000394721 - 2¹ = 1000394719 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1000394723) 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 in 5 ways as a sum of consecutive naturals, for example, 55577476 + ... + 55577493.

Almost surely, 2^1000394721 is an apocalyptic number.

It is an amenable number.

1000394721 is a deficient number, since it is larger than the sum of its proper divisors (444619889).

1000394721 is a wasteful number, since it uses less digits than its factorization.

1000394721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 111154975 (or 111154972 counting only the distinct ones).

The product of its (nonzero) digits is 1512, while the sum is 27.

The square root of 1000394721 is about 31629.0170729348. The cubic root of 1000394721 is about 1000.1315563588.

The spelling of 1000394721 in words is "one billion, three hundred ninety-four thousand, seven hundred twenty-one".