651610011581 has 4 divisors (see below), whose sum is σ = 652672997532. Its totient is φ = 650547025632.

The previous prime is 651610011511. The next prime is 651610011659. The reversal of 651610011581 is 185110016156.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 205058631556 + 446551380025 = 452834^2 + 668245^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-651610011581 is a prime.

It is a super-2 number, since 2×651610011581² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (651610011511) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 531492056 + ... + 531493281.

It is an arithmetic number, because the mean of its divisors is an integer number (163168249383).

Almost surely, 2^651610011581 is an apocalyptic number.

It is an amenable number.

651610011581 is a deficient number, since it is larger than the sum of its proper divisors (1062985951).

651610011581 is a wasteful number, since it uses less digits than its factorization.

651610011581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1062985950.

The product of its (nonzero) digits is 7200, while the sum is 35.

The spelling of 651610011581 in words is "six hundred fifty-one billion, six hundred ten million, eleven thousand, five hundred eighty-one".