645670426 has 8 divisors (see below), whose sum is σ = 1019479680. Its totient is φ = 305843868.

The previous prime is 645670423. The next prime is 645670447. The reversal of 645670426 is 624076546.

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

It is a super-2 number, since 2×645670426² = 833780598022042952, which contains 22 as substring.

It is a zygodrome in base 3.

It is not an unprimeable number, because it can be changed into a prime (645670423) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8495626 + ... + 8495701.

It is an arithmetic number, because the mean of its divisors is an integer number (127434960).

Almost surely, 2^645670426 is an apocalyptic number.

645670426 is a deficient number, since it is larger than the sum of its proper divisors (373809254).

645670426 is a wasteful number, since it uses less digits than its factorization.

645670426 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16991348.

The product of its (nonzero) digits is 241920, while the sum is 40.

The square root of 645670426 is about 25410.0457693409. The cubic root of 645670426 is about 864.3115133640.

The spelling of 645670426 in words is "six hundred forty-five million, six hundred seventy thousand, four hundred twenty-six".