213281978526 has 40 divisors (see below), whose sum is σ = 490826108520. Its totient is φ = 69172531632.

The previous prime is 213281978521. The next prime is 213281978527. The reversal of 213281978526 is 625879182312.

213281978526 is a `hidden beast` number, since 2 + 1 + 3 + 28 + 1 + 97 + 8 + 526 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (213281978521) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 17785296 + ... + 17797283.

It is an arithmetic number, because the mean of its divisors is an integer number (12270652713).

Almost surely, 2^213281978526 is an apocalyptic number.

213281978526 is an abundant number, since it is smaller than the sum of its proper divisors (277544129994).

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

213281978526 is a wasteful number, since it uses less digits than its factorization.

213281978526 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35582630 (or 35582621 counting only the distinct ones).

The product of its digits is 2903040, while the sum is 54.

The spelling of 213281978526 in words is "two hundred thirteen billion, two hundred eighty-one million, nine hundred seventy-eight thousand, five hundred twenty-six".