20001666722 has 4 divisors (see below), whose sum is σ = 30002500086. Its totient is φ = 10000833360.

The previous prime is 20001666721. The next prime is 20001666731. The reversal of 20001666722 is 22766610002.

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

It can be written as a sum of positive squares in only one way, i.e., 16871152321 + 3130514401 = 129889^2 + 55951^2 .

It is not an unprimeable number, because it can be changed into a prime (20001666721) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5000416679 + ... + 5000416682.

Almost surely, 2^20001666722 is an apocalyptic number.

20001666722 is a deficient number, since it is larger than the sum of its proper divisors (10000833364).

20001666722 is a wasteful number, since it uses less digits than its factorization.

20001666722 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10000833363.

The product of its (nonzero) digits is 12096, while the sum is 32.

The spelling of 20001666722 in words is "twenty billion, one million, six hundred sixty-six thousand, seven hundred twenty-two".