20402231461 has 2 divisors, whose sum is σ = 20402231462. Its totient is φ = 20402231460.

The previous prime is 20402231429. The next prime is 20402231501. The reversal of 20402231461 is 16413220402.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15170602561 + 5231628900 = 123169^2 + 72330^2 .

It is a cyclic number.

It is not a de Polignac number, because 20402231461 - 2⁵ = 20402231429 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20402231561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10201115730 + 10201115731.

It is an arithmetic number, because the mean of its divisors is an integer number (10201115731).

Almost surely, 2^20402231461 is an apocalyptic number.

It is an amenable number.

20402231461 is a deficient number, since it is larger than the sum of its proper divisors (1).

20402231461 is an equidigital number, since it uses as much as digits as its factorization.

20402231461 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2304, while the sum is 25.

Adding to 20402231461 its reverse (16413220402), we get a palindrome (36815451863).

The spelling of 20402231461 in words is "twenty billion, four hundred two million, two hundred thirty-one thousand, four hundred sixty-one".