20665415642 has 8 divisors (see below), whose sum is σ = 30998734932. Its totient is φ = 10332504000.

The previous prime is 20665415599. The next prime is 20665415653. The reversal of 20665415642 is 24651456602.

It can be written as a sum of positive squares in 2 ways, for example, as 20586223441 + 79192201 = 143479^2 + 8899^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a self number, because there is not a number n which added to its sum of digits gives 20665415642.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 134642 + ... + 243842.

Almost surely, 2^20665415642 is an apocalyptic number.

20665415642 is a deficient number, since it is larger than the sum of its proper divisors (10333319290).

20665415642 is a wasteful number, since it uses less digits than its factorization.

20665415642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 203824.

The product of its (nonzero) digits is 345600, while the sum is 41.

The spelling of 20665415642 in words is "twenty billion, six hundred sixty-five million, four hundred fifteen thousand, six hundred forty-two".