661066151565 has 16 divisors (see below), whose sum is σ = 1086292487808. Its totient is φ = 343039732416.

The previous prime is 661066151561. The next prime is 661066151609. The reversal of 661066151565 is 565151660166.

It is not a de Polignac number, because 661066151565 - 2² = 661066151561 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661066151561) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 595554537 + ... + 595555646.

It is an arithmetic number, because the mean of its divisors is an integer number (67893280488).

Almost surely, 2^661066151565 is an apocalyptic number.

It is an amenable number.

661066151565 is a deficient number, since it is larger than the sum of its proper divisors (425226336243).

661066151565 is a wasteful number, since it uses less digits than its factorization.

661066151565 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1191110228.

The product of its (nonzero) digits is 972000, while the sum is 48.

The spelling of 661066151565 in words is "six hundred sixty-one billion, sixty-six million, one hundred fifty-one thousand, five hundred sixty-five".