651075215261 has 4 divisors (see below), whose sum is σ = 651076837632. Its totient is φ = 651073592892.

The previous prime is 651075215257. The next prime is 651075215279. The reversal of 651075215261 is 162512570156.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 651075215261 - 2² = 651075215257 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (651075215251) 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, 280580 + ... + 1175106.

It is an arithmetic number, because the mean of its divisors is an integer number (162769209408).

Almost surely, 2^651075215261 is an apocalyptic number.

It is an amenable number.

651075215261 is a deficient number, since it is larger than the sum of its proper divisors (1622371).

651075215261 is an equidigital number, since it uses as much as digits as its factorization.

651075215261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1622370.

The product of its (nonzero) digits is 126000, while the sum is 41.

The spelling of 651075215261 in words is "six hundred fifty-one billion, seventy-five million, two hundred fifteen thousand, two hundred sixty-one".