51281273651436 has 144 divisors (see below), whose sum is σ = 141992943805440. Its totient is φ = 15532680683520.

The previous prime is 51281273651383. The next prime is 51281273651441. The reversal of 51281273651436 is 63415637218215.

It is a happy number.

51281273651436 is a `hidden beast` number, since 5 + 1 + 2 + 8 + 127 + 36 + 51 + 436 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 411105556 + ... + 411230276.

It is an arithmetic number, because the mean of its divisors is an integer number (986062109760).

Almost surely, 2^{51281273651436} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51281273651436, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (70996471902720).

51281273651436 is an abundant number, since it is smaller than the sum of its proper divisors (90711670154004).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

51281273651436 is a wasteful number, since it uses less digits than its factorization.

51281273651436 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 147944 (or 147939 counting only the distinct ones).

The product of its digits is 7257600, while the sum is 54.

The spelling of 51281273651436 in words is "fifty-one trillion, two hundred eighty-one billion, two hundred seventy-three million, six hundred fifty-one thousand, four hundred thirty-six".