613995921 has 72 divisors (see below), whose sum is σ = 1149842304. Its totient is φ = 312056640.

The previous prime is 613995881. The next prime is 613995923. The reversal of 613995921 is 129599316.

It is a happy number.

613995921 is a `hidden beast` number, since 613 + 9 + 9 + 5 + 9 + 21 = 666.

It is not a de Polignac number, because 613995921 - 2¹³ = 613987729 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (613995923) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 226651 + ... + 229343.

It is an arithmetic number, because the mean of its divisors is an integer number (15970032).

Almost surely, 2^613995921 is an apocalyptic number.

It is an amenable number.

613995921 is a deficient number, since it is larger than the sum of its proper divisors (535846383).

613995921 is a wasteful number, since it uses less digits than its factorization.

613995921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2771 (or 2761 counting only the distinct ones).

The product of its digits is 131220, while the sum is 45.

The square root of 613995921 is about 24778.9410790695. The cubic root of 613995921 is about 849.9404438088.

The spelling of 613995921 in words is "six hundred thirteen million, nine hundred ninety-five thousand, nine hundred twenty-one".