51742249856 has 64 divisors (see below), whose sum is σ = 112508904960. Its totient is φ = 23507136000.

The previous prime is 51742249843. The next prime is 51742249927. The reversal of 51742249856 is 65894224715.

It is a tau number, because it is divible by the number of its divisors (64).

It is a junction number, because it is equal to n+sod(n) for n = 51742249798 and 51742249807.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3099131 + ... + 3115781.

It is an arithmetic number, because the mean of its divisors is an integer number (1757951640).

Almost surely, 2^51742249856 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 51742249856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (56254452480).

51742249856 is an abundant number, since it is smaller than the sum of its proper divisors (60766655104).

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

51742249856 is a wasteful number, since it uses less digits than its factorization.

51742249856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18883 (or 18871 counting only the distinct ones).

The product of its digits is 4838400, while the sum is 53.

The spelling of 51742249856 in words is "fifty-one billion, seven hundred forty-two million, two hundred forty-nine thousand, eight hundred fifty-six".