645747401 has 8 divisors (see below), whose sum is σ = 697260480. Its totient is φ = 594497232.

The previous prime is 645747373. The next prime is 645747413. The reversal of 645747401 is 104747546.

It is a happy number.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-645747401 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (645747481) 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, 60605 + ... + 70458.

It is an arithmetic number, because the mean of its divisors is an integer number (87157560).

Almost surely, 2^645747401 is an apocalyptic number.

It is an amenable number.

645747401 is a deficient number, since it is larger than the sum of its proper divisors (51513079).

645747401 is a wasteful number, since it uses less digits than its factorization.

645747401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 131455.

The product of its (nonzero) digits is 94080, while the sum is 38.

The square root of 645747401 is about 25411.5603810549. The cubic root of 645747401 is about 864.3458589230.

The spelling of 645747401 in words is "six hundred forty-five million, seven hundred forty-seven thousand, four hundred one".