611001701561 has 2 divisors, whose sum is σ = 611001701562. Its totient is φ = 611001701560.

The previous prime is 611001701551. The next prime is 611001701587. The reversal of 611001701561 is 165107100116.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 428574478336 + 182427223225 = 654656^2 + 427115^2 .

It is a cyclic number.

It is not a de Polignac number, because 611001701561 - 2²² = 610997507257 is a prime.

It is not a weakly prime, because it can be changed into another prime (611001701551) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 305500850780 + 305500850781.

It is an arithmetic number, because the mean of its divisors is an integer number (305500850781).

Almost surely, 2^611001701561 is an apocalyptic number.

It is an amenable number.

611001701561 is a deficient number, since it is larger than the sum of its proper divisors (1).

611001701561 is an equidigital number, since it uses as much as digits as its factorization.

611001701561 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1260, while the sum is 29.

Adding to 611001701561 its reverse (165107100116), we get a palindrome (776108801677).

The spelling of 611001701561 in words is "six hundred eleven billion, one million, seven hundred one thousand, five hundred sixty-one".