851461724621 has 4 divisors (see below), whose sum is σ = 851484828252. Its totient is φ = 851438620992.

The previous prime is 851461724573. The next prime is 851461724653. The reversal of 851461724621 is 126427164158.

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 752233574596 + 99228150025 = 867314^2 + 315005^2 .

It is a cyclic number.

It is not a de Polignac number, because 851461724621 - 2⁶ = 851461724557 is a prime.

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 (851461724671) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11496446 + ... + 11570271.

It is an arithmetic number, because the mean of its divisors is an integer number (212871207063).

Almost surely, 2^851461724621 is an apocalyptic number.

It is an amenable number.

851461724621 is a deficient number, since it is larger than the sum of its proper divisors (23103631).

851461724621 is a wasteful number, since it uses less digits than its factorization.

851461724621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23103630.

The product of its digits is 645120, while the sum is 47.

Adding to 851461724621 its reverse (126427164158), we get a palindrome (977888888779).

The spelling of 851461724621 in words is "eight hundred fifty-one billion, four hundred sixty-one million, seven hundred twenty-four thousand, six hundred twenty-one".