20666222421 has 16 divisors (see below), whose sum is σ = 29682058560. Its totient is φ = 12714468480.

The previous prime is 20666222417. The next prime is 20666222429. The reversal of 20666222421 is 12422266602.

It is not a de Polignac number, because 20666222421 - 2² = 20666222417 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20666222429) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 94785 + ... + 224313.

It is an arithmetic number, because the mean of its divisors is an integer number (1855128660).

Almost surely, 2^20666222421 is an apocalyptic number.

It is an amenable number.

20666222421 is a deficient number, since it is larger than the sum of its proper divisors (9015836139).

20666222421 is a wasteful number, since it uses less digits than its factorization.

20666222421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 133636.

The product of its (nonzero) digits is 27648, while the sum is 33.

The spelling of 20666222421 in words is "twenty billion, six hundred sixty-six million, two hundred twenty-two thousand, four hundred twenty-one".