20310146561 has 4 divisors (see below), whose sum is σ = 20311483092. Its totient is φ = 20308810032.

The previous prime is 20310146557. The next prime is 20310146569. The reversal of 20310146561 is 16564101302.

It is a happy number.

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 6959730625 + 13350415936 = 83425^2 + 115544^2 .

It is a cyclic number.

It is not a de Polignac number, because 20310146561 - 2² = 20310146557 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20310146569) 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, 645206 + ... + 675951.

It is an arithmetic number, because the mean of its divisors is an integer number (5077870773).

Almost surely, 2^20310146561 is an apocalyptic number.

It is an amenable number.

20310146561 is a deficient number, since it is larger than the sum of its proper divisors (1336531).

20310146561 is a wasteful number, since it uses less digits than its factorization.

20310146561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1336530.

The product of its (nonzero) digits is 4320, while the sum is 29.

Adding to 20310146561 its reverse (16564101302), we get a palindrome (36874247863).

The spelling of 20310146561 in words is "twenty billion, three hundred ten million, one hundred forty-six thousand, five hundred sixty-one".