2651561465261 has 2 divisors, whose sum is σ = 2651561465262. Its totient is φ = 2651561465260.

The previous prime is 2651561465257. The next prime is 2651561465321. The reversal of 2651561465261 is 1625641651562.

2651561465261 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2623975577161 + 27585888100 = 1619869^2 + 166090^2 .

It is a cyclic number.

It is not a de Polignac number, because 2651561465261 - 2² = 2651561465257 is a prime.

It is a super-2 number, since 2×2651561465261² (a number of 26 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2651561465251) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1325780732630 + 1325780732631.

It is an arithmetic number, because the mean of its divisors is an integer number (1325780732631).

Almost surely, 2^{2651561465261} is an apocalyptic number.

It is an amenable number.

2651561465261 is a deficient number, since it is larger than the sum of its proper divisors (1).

2651561465261 is an equidigital number, since it uses as much as digits as its factorization.

2651561465261 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2592000, while the sum is 50.

The spelling of 2651561465261 in words is "two trillion, six hundred fifty-one billion, five hundred sixty-one million, four hundred sixty-five thousand, two hundred sixty-one".