20351340291 has 4 divisors (see below), whose sum is σ = 27135120392. Its totient is φ = 13567560192.

The previous prime is 20351340283. The next prime is 20351340299. The reversal of 20351340291 is 19204315302.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (20351340283) and next prime (20351340299).

It is not a de Polignac number, because 20351340291 - 2³ = 20351340283 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20351340299) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3391890046 + ... + 3391890051.

It is an arithmetic number, because the mean of its divisors is an integer number (6783780098).

Almost surely, 2^20351340291 is an apocalyptic number.

20351340291 is a deficient number, since it is larger than the sum of its proper divisors (6783780101).

20351340291 is an equidigital number, since it uses as much as digits as its factorization.

20351340291 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6783780100.

The product of its (nonzero) digits is 6480, while the sum is 30.

Adding to 20351340291 its reverse (19204315302), we get a palindrome (39555655593).

The spelling of 20351340291 in words is "twenty billion, three hundred fifty-one million, three hundred forty thousand, two hundred ninety-one".