20401226665 has 32 divisors (see below), whose sum is σ = 26068386816. Its totient is φ = 15292992000.

The previous prime is 20401226647. The next prime is 20401226723. The reversal of 20401226665 is 56662210402.

It is not a de Polignac number, because 20401226665 - 2¹¹ = 20401224617 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20401226665.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4575117 + ... + 4579573.

It is an arithmetic number, because the mean of its divisors is an integer number (814637088).

Almost surely, 2^20401226665 is an apocalyptic number.

It is an amenable number.

20401226665 is a deficient number, since it is larger than the sum of its proper divisors (5667160151).

20401226665 is a wasteful number, since it uses less digits than its factorization.

20401226665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5289.

The product of its (nonzero) digits is 34560, while the sum is 34.

The spelling of 20401226665 in words is "twenty billion, four hundred one million, two hundred twenty-six thousand, six hundred sixty-five".