20721670330 has 16 divisors (see below), whose sum is σ = 38166426144. Its totient is φ = 8095908240.

The previous prime is 20721670327. The next prime is 20721670331. The reversal of 20721670330 is 3307612702.

It is a junction number, because it is equal to n+sod(n) for n = 20721670292 and 20721670301.

It is not an unprimeable number, because it can be changed into a prime (20721670331) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 24094536 + ... + 24095395.

It is an arithmetic number, because the mean of its divisors is an integer number (2385401634).

Almost surely, 2^20721670330 is an apocalyptic number.

20721670330 is a deficient number, since it is larger than the sum of its proper divisors (17444755814).

20721670330 is a wasteful number, since it uses less digits than its factorization.

20721670330 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 48189981.

The product of its (nonzero) digits is 10584, while the sum is 31.

The spelling of 20721670330 in words is "twenty billion, seven hundred twenty-one million, six hundred seventy thousand, three hundred thirty".