640020046 has 16 divisors (see below), whose sum is σ = 1031677776. Its totient is φ = 296689536.

The previous prime is 640020013. The next prime is 640020047.

640020046 is nontrivially palindromic in base 10.

It is a junction number, because it is equal to n+sod(n) for n = 640019999 and 640020026.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640020047) 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, 138201 + ... + 142756.

It is an arithmetic number, because the mean of its divisors is an integer number (64479861).

Almost surely, 2^640020046 is an apocalyptic number.

640020046 is a deficient number, since it is larger than the sum of its proper divisors (391657730).

640020046 is a wasteful number, since it uses less digits than its factorization.

640020046 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 281043.

The product of its (nonzero) digits is 1152, while the sum is 22.

The square root of 640020046 is about 25298.6174721070. The cubic root of 640020046 is about 861.7828733767.

The spelling of 640020046 in words is "six hundred forty million, twenty thousand, forty-six".