640700001 has 6 divisors (see below), whose sum is σ = 925455570. Its totient is φ = 427133328.

The previous prime is 640699993. The next prime is 640700003. The reversal of 640700001 is 100007046.

It can be written as a sum of positive squares in only one way, i.e., 622552401 + 18147600 = 24951^2 + 4260^2 .

It is not a de Polignac number, because 640700001 - 2³ = 640699993 is a prime.

It is not an unprimeable number, because it can be changed into a prime (640700003) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 35594436 + ... + 35594453.

It is an arithmetic number, because the mean of its divisors is an integer number (154242595).

Almost surely, 2^640700001 is an apocalyptic number.

It is an amenable number.

640700001 is a deficient number, since it is larger than the sum of its proper divisors (284755569).

640700001 is a wasteful number, since it uses less digits than its factorization.

640700001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71188895 (or 71188892 counting only the distinct ones).

The product of its (nonzero) digits is 168, while the sum is 18.

The square root of 640700001 is about 25312.0524849329. The cubic root of 640700001 is about 862.0879503753.

Adding to 640700001 its reverse (100007046), we get a palindrome (740707047).

The spelling of 640700001 in words is "six hundred forty million, seven hundred thousand, one".