3420147121681 has 2 divisors, whose sum is σ = 3420147121682. Its totient is φ = 3420147121680.

The previous prime is 3420147121679. The next prime is 3420147121813. The reversal of 3420147121681 is 1861217410243.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2644266254400 + 775880867281 = 1626120^2 + 880841^2 .

It is a cyclic number.

It is not a de Polignac number, because 3420147121681 - 2¹ = 3420147121679 is a prime.

It is a super-2 number, since 2×3420147121681² (a number of 26 digits) contains 22 as substring.

Together with 3420147121679, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (3420147121981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1710073560840 + 1710073560841.

It is an arithmetic number, because the mean of its divisors is an integer number (1710073560841).

Almost surely, 2^{3420147121681} is an apocalyptic number.

It is an amenable number.

3420147121681 is a deficient number, since it is larger than the sum of its proper divisors (1).

3420147121681 is an equidigital number, since it uses as much as digits as its factorization.

3420147121681 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 64512, while the sum is 40.

The spelling of 3420147121681 in words is "three trillion, four hundred twenty billion, one hundred forty-seven million, one hundred twenty-one thousand, six hundred eighty-one".