20315101426661 has 4 divisors (see below), whose sum is σ = 20316724440012. Its totient is φ = 20313478413312.

The previous prime is 20315101426651. The next prime is 20315101426673. The reversal of 20315101426661 is 16662410151302.

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

It can be written as a sum of positive squares in 2 ways, for example, as 14226520501636 + 6088580925025 = 3771806^2 + 2467505^2 .

It is a cyclic number.

It is not a de Polignac number, because 20315101426661 - 2¹⁸ = 20315101164517 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 (20315101426651) 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, 811487900 + ... + 811512933.

It is an arithmetic number, because the mean of its divisors is an integer number (5079181110003).

Almost surely, 2^{20315101426661} is an apocalyptic number.

It is an amenable number.

20315101426661 is a deficient number, since it is larger than the sum of its proper divisors (1623013351).

20315101426661 is a wasteful number, since it uses less digits than its factorization.

20315101426661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1623013350.

The product of its (nonzero) digits is 51840, while the sum is 38.

Adding to 20315101426661 its reverse (16662410151302), we get a palindrome (36977511577963).

The spelling of 20315101426661 in words is "twenty trillion, three hundred fifteen billion, one hundred one million, four hundred twenty-six thousand, six hundred sixty-one".