21655252023206 has 16 divisors (see below), whose sum is σ = 32875879503600. Its totient is φ = 10696638549888.

The previous prime is 21655252023131. The next prime is 21655252023227. The reversal of 21655252023206 is 60232025255612.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 87890 + ... + 6581658.

It is an arithmetic number, because the mean of its divisors is an integer number (2054742468975).

Almost surely, 2^{21655252023206} is an apocalyptic number.

21655252023206 is a deficient number, since it is larger than the sum of its proper divisors (11220627480394).

21655252023206 is a wasteful number, since it uses less digits than its factorization.

21655252023206 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6513943.

The product of its (nonzero) digits is 432000, while the sum is 41.

Adding to 21655252023206 its reverse (60232025255612), we get a palindrome (81887277278818).

The spelling of 21655252023206 in words is "twenty-one trillion, six hundred fifty-five billion, two hundred fifty-two million, twenty-three thousand, two hundred six".