646757641 has 8 divisors (see below), whose sum is σ = 653899968. Its totient is φ = 639630000.

The previous prime is 646757621. The next prime is 646757651. The reversal of 646757641 is 146757646.

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 646757641 - 2⁷ = 646757513 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 646757591 and 646757600.

It is not an unprimeable number, because it can be changed into a prime (646757621) 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, 101026 + ... + 107236.

It is an arithmetic number, because the mean of its divisors is an integer number (81737496).

Almost surely, 2^646757641 is an apocalyptic number.

It is an amenable number.

646757641 is a deficient number, since it is larger than the sum of its proper divisors (7142327).

646757641 is a wasteful number, since it uses less digits than its factorization.

646757641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7343.

The product of its digits is 846720, while the sum is 46.

The square root of 646757641 is about 25431.4301799958. The cubic root of 646757641 is about 864.7963662456.

The spelling of 646757641 in words is "six hundred forty-six million, seven hundred fifty-seven thousand, six hundred forty-one".