640261101 has 8 divisors (see below), whose sum is σ = 883118880. Its totient is φ = 412122032.

The previous prime is 640261093. The next prime is 640261103. The reversal of 640261101 is 101162046.

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 640261101 - 2³ = 640261093 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640261103) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3679575 + ... + 3679748.

It is an arithmetic number, because the mean of its divisors is an integer number (110389860).

Almost surely, 2^640261101 is an apocalyptic number.

It is an amenable number.

640261101 is a deficient number, since it is larger than the sum of its proper divisors (242857779).

640261101 is a wasteful number, since it uses less digits than its factorization.

640261101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7359355.

The product of its (nonzero) digits is 288, while the sum is 21.

The square root of 640261101 is about 25303.3812167465. The cubic root of 640261101 is about 861.8910527985.

The spelling of 640261101 in words is "six hundred forty million, two hundred sixty-one thousand, one hundred one".