51500070 has 64 divisors (see below), whose sum is σ = 144576000. Its totient is φ = 13009248.

The previous prime is 51500069. The next prime is 51500077. The reversal of 51500070 is 7000515.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51500077) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 111 + ... + 10149.

It is an arithmetic number, because the mean of its divisors is an integer number (2259000).

Almost surely, 2^51500070 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51500070, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (72288000).

51500070 is an abundant number, since it is smaller than the sum of its proper divisors (93075930).

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

51500070 is a wasteful number, since it uses less digits than its factorization.

51500070 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10074 (or 10068 counting only the distinct ones).

The product of its (nonzero) digits is 175, while the sum is 18.

The square root of 51500070 is about 7176.3549243331. The cubic root of 51500070 is about 372.0511116035.

Adding to 51500070 its reverse (7000515), we get a palindrome (58500585).

The spelling of 51500070 in words is "fifty-one million, five hundred thousand, seventy".