675642721 has 8 divisors (see below), whose sum is σ = 732851840. Its totient is φ = 619181712.

The previous prime is 675642697. The next prime is 675642743. The reversal of 675642721 is 127246576.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 675642721 - 2¹³ = 675634529 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (675642791) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 185145 + ... + 188758.

It is an arithmetic number, because the mean of its divisors is an integer number (91606480).

Almost surely, 2^675642721 is an apocalyptic number.

It is an amenable number.

675642721 is a deficient number, since it is larger than the sum of its proper divisors (57209119).

675642721 is a wasteful number, since it uses less digits than its factorization.

675642721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 374055.

The product of its digits is 141120, while the sum is 40.

The square root of 675642721 is about 25993.1283419291. The cubic root of 675642721 is about 877.4836520467.

The spelling of 675642721 in words is "six hundred seventy-five million, six hundred forty-two thousand, seven hundred twenty-one".