20401420397 has 2 divisors, whose sum is σ = 20401420398. Its totient is φ = 20401420396.

The previous prime is 20401420393. The next prime is 20401420513. The reversal of 20401420397 is 79302410402.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13725059716 + 6676360681 = 117154^2 + 81709^2 .

It is a cyclic number.

It is not a de Polignac number, because 20401420397 - 2² = 20401420393 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20401420393) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10200710198 + 10200710199.

It is an arithmetic number, because the mean of its divisors is an integer number (10200710199).

Almost surely, 2^20401420397 is an apocalyptic number.

It is an amenable number.

20401420397 is a deficient number, since it is larger than the sum of its proper divisors (1).

20401420397 is an equidigital number, since it uses as much as digits as its factorization.

20401420397 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12096, while the sum is 32.

Adding to 20401420397 its reverse (79302410402), we get a palindrome (99703830799).

The spelling of 20401420397 in words is "twenty billion, four hundred one million, four hundred twenty thousand, three hundred ninety-seven".