1640021635423 has 16 divisors (see below), whose sum is σ = 1718181763200. Its totient is φ = 1563305103360.

The previous prime is 1640021635409. The next prime is 1640021635457. The reversal of 1640021635423 is 3245361200461.

It is a cyclic number.

It is not a de Polignac number, because 1640021635423 - 2⁵ = 1640021635391 is a prime.

It is a super-3 number, since 3×1640021635423³ (a number of 38 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1640021635463) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 48371265 + ... + 48405157.

It is an arithmetic number, because the mean of its divisors is an integer number (107386360200).

Almost surely, 2^{1640021635423} is an apocalyptic number.

1640021635423 is a deficient number, since it is larger than the sum of its proper divisors (78160127777).

1640021635423 is a wasteful number, since it uses less digits than its factorization.

1640021635423 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55122.

The product of its (nonzero) digits is 103680, while the sum is 37.

Adding to 1640021635423 its reverse (3245361200461), we get a palindrome (4885382835884).

The spelling of 1640021635423 in words is "one trillion, six hundred forty billion, twenty-one million, six hundred thirty-five thousand, four hundred twenty-three".