2661406433551 has 2 divisors, whose sum is σ = 2661406433552. Its totient is φ = 2661406433550.

The previous prime is 2661406433513. The next prime is 2661406433579. The reversal of 2661406433551 is 1553346041662.

2661406433551 is digitally balanced in base 2 and base 3, because in such bases it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 2661406433551 - 2⁹ = 2661406433039 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2661406433501) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1330703216775 + 1330703216776.

It is an arithmetic number, because the mean of its divisors is an integer number (1330703216776).

Almost surely, 2^{2661406433551} is an apocalyptic number.

2661406433551 is a deficient number, since it is larger than the sum of its proper divisors (1).

2661406433551 is an equidigital number, since it uses as much as digits as its factorization.

2661406433551 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1555200, while the sum is 46.

The spelling of 2661406433551 in words is "two trillion, six hundred sixty-one billion, four hundred six million, four hundred thirty-three thousand, five hundred fifty-one".