20581884515851 has 8 divisors (see below), whose sum is σ = 21291891717600. Its totient is φ = 19871896450560.

The previous prime is 20581884515783. The next prime is 20581884515879. The reversal of 20581884515851 is 15851548818502.

It is a happy number.

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

It is not a de Polignac number, because 20581884515851 - 2⁷ = 20581884515723 is a prime.

It is a super-2 number, since 2×20581884515851² (a number of 27 digits) contains 22 as substring.

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 20581884515851.

It is not an unprimeable number, because it can be changed into a prime (20581884515891) 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, 2578710 + ... + 6914731.

It is an arithmetic number, because the mean of its divisors is an integer number (2661486464700).

Almost surely, 2^{20581884515851} is an apocalyptic number.

20581884515851 is a deficient number, since it is larger than the sum of its proper divisors (710007201749).

20581884515851 is an equidigital number, since it uses as much as digits as its factorization.

20581884515851 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9568229.

The product of its (nonzero) digits is 20480000, while the sum is 61.

The spelling of 20581884515851 in words is "twenty trillion, five hundred eighty-one billion, eight hundred eighty-four million, five hundred fifteen thousand, eight hundred fifty-one".