20400515217371 has 2 divisors, whose sum is σ = 20400515217372. Its totient is φ = 20400515217370.

The previous prime is 20400515217353. The next prime is 20400515217443. The reversal of 20400515217371 is 17371251500402.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20400515217371 - 2¹⁴ = 20400515200987 is a prime.

It is a super-2 number, since 2×20400515217371² (a number of 27 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (20400515217571) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10200257608685 + 10200257608686.

It is an arithmetic number, because the mean of its divisors is an integer number (10200257608686).

Almost surely, 2^{20400515217371} is an apocalyptic number.

20400515217371 is a deficient number, since it is larger than the sum of its proper divisors (1).

20400515217371 is an equidigital number, since it uses as much as digits as its factorization.

20400515217371 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 58800, while the sum is 38.

Adding to 20400515217371 its reverse (17371251500402), we get a palindrome (37771766717773).

The spelling of 20400515217371 in words is "twenty trillion, four hundred billion, five hundred fifteen million, two hundred seventeen thousand, three hundred seventy-one".