213500401640 has 16 divisors (see below), whose sum is σ = 480375903780. Its totient is φ = 85400160640.

The previous prime is 213500401633. The next prime is 213500401649. The reversal of 213500401640 is 46104005312.

It can be written as a sum of positive squares in 2 ways, for example, as 207802869316 + 5697532324 = 455854^2 + 75482^2 .

It is not an unprimeable number, because it can be changed into a prime (213500401649) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2668754981 + ... + 2668755060.

Almost surely, 2^213500401640 is an apocalyptic number.

213500401640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

213500401640 is an abundant number, since it is smaller than the sum of its proper divisors (266875502140).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

213500401640 is a wasteful number, since it uses less digits than its factorization.

213500401640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5337510052 (or 5337510048 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 26.

Adding to 213500401640 its reverse (46104005312), we get a palindrome (259604406952).

The spelling of 213500401640 in words is "two hundred thirteen billion, five hundred million, four hundred one thousand, six hundred forty".