20366401721 has 16 divisors (see below), whose sum is σ = 21470375808. Its totient is φ = 19280976000.

The previous prime is 20366401711. The next prime is 20366401733. The reversal of 20366401721 is 12710466302.

It is a cyclic number.

It is not a de Polignac number, because 20366401721 - 2¹⁴ = 20366385337 is a prime.

It is a super-2 number, since 2×20366401721² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20366401711) 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, 3198581 + ... + 3204941.

It is an arithmetic number, because the mean of its divisors is an integer number (1341898488).

Almost surely, 2^20366401721 is an apocalyptic number.

It is an amenable number.

20366401721 is a deficient number, since it is larger than the sum of its proper divisors (1103974087).

20366401721 is a wasteful number, since it uses less digits than its factorization.

20366401721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7792.

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

The spelling of 20366401721 in words is "twenty billion, three hundred sixty-six million, four hundred one thousand, seven hundred twenty-one".