20671250021 has 8 divisors (see below), whose sum is σ = 21254679840. Its totient is φ = 20089122768.

The previous prime is 20671249993. The next prime is 20671250029. The reversal of 20671250021 is 12005217602.

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

It is not a de Polignac number, because 20671250021 - 2⁶ = 20671249957 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20671250029) 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, 293411 + ... + 356976.

It is an arithmetic number, because the mean of its divisors is an integer number (2656834980).

Almost surely, 2^20671250021 is an apocalyptic number.

It is an amenable number.

20671250021 is a deficient number, since it is larger than the sum of its proper divisors (583429819).

20671250021 is an equidigital number, since it uses as much as digits as its factorization.

20671250021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 651283.

The product of its (nonzero) digits is 1680, while the sum is 26.

Adding to 20671250021 its reverse (12005217602), we get a palindrome (32676467623).

The spelling of 20671250021 in words is "twenty billion, six hundred seventy-one million, two hundred fifty thousand, twenty-one".