51215135206 has 4 divisors (see below), whose sum is σ = 76822702812. Its totient is φ = 25607567602.

The previous prime is 51215135203. The next prime is 51215135239. The reversal of 51215135206 is 60253151215.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51215135203) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12803783800 + ... + 12803783803.

It is an arithmetic number, because the mean of its divisors is an integer number (19205675703).

Almost surely, 2^51215135206 is an apocalyptic number.

51215135206 is a deficient number, since it is larger than the sum of its proper divisors (25607567606).

51215135206 is a wasteful number, since it uses less digits than its factorization.

51215135206 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25607567605.

The product of its (nonzero) digits is 9000, while the sum is 31.

The spelling of 51215135206 in words is "fifty-one billion, two hundred fifteen million, one hundred thirty-five thousand, two hundred six".