21770634206 has 4 divisors (see below), whose sum is σ = 32655951312. Its totient is φ = 10885317102.

The previous prime is 21770634191. The next prime is 21770634209. The reversal of 21770634206 is 60243607712.

It is a semiprime because it is the product of two primes.

It is a self number, because there is not a number n which added to its sum of digits gives 21770634206.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21770634209) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5442658550 + ... + 5442658553.

It is an arithmetic number, because the mean of its divisors is an integer number (8163987828).

Almost surely, 2^21770634206 is an apocalyptic number.

21770634206 is a deficient number, since it is larger than the sum of its proper divisors (10885317106).

21770634206 is a wasteful number, since it uses less digits than its factorization.

21770634206 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10885317105.

The product of its (nonzero) digits is 84672, while the sum is 38.

The spelling of 21770634206 in words is "twenty-one billion, seven hundred seventy million, six hundred thirty-four thousand, two hundred six".