20520235666406 has 8 divisors (see below), whose sum is σ = 35177546856720. Its totient is φ = 8794386714168.

The previous prime is 20520235666393. The next prime is 20520235666433. The reversal of 20520235666406 is 60466653202502.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 732865559501 + ... + 732865559528.

It is an arithmetic number, because the mean of its divisors is an integer number (4397193357090).

Almost surely, 2^{20520235666406} is an apocalyptic number.

20520235666406 is a deficient number, since it is larger than the sum of its proper divisors (14657311190314).

20520235666406 is a wasteful number, since it uses less digits than its factorization.

20520235666406 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1465731119038.

The product of its (nonzero) digits is 3110400, while the sum is 47.

Adding to 20520235666406 its reverse (60466653202502), we get a palindrome (80986888868908).

The spelling of 20520235666406 in words is "twenty trillion, five hundred twenty billion, two hundred thirty-five million, six hundred sixty-six thousand, four hundred six".