51123072 has 384 divisors, whose sum is σ = 195350400. Its totient is φ = 11612160.

The previous prime is 51123067. The next prime is 51123073. The reversal of 51123072 is 27032115.

It is a tau number, because it is divible by the number of its divisors (384).

It is a super-2 number, since 2×51123072² = 5227136981434368, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51123073) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2690679 + ... + 2690697.

It is an arithmetic number, because the mean of its divisors is an integer number (508725).

Almost surely, 2^51123072 is an apocalyptic number.

51123072 is a gapful number since it is divisible by the number (52) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51123072, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (97675200).

51123072 is an abundant number, since it is smaller than the sum of its proper divisors (144227328).

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

51123072 is a wasteful number, since it uses less digits than its factorization.

51123072 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 74 (or 55 counting only the distinct ones).

The product of its (nonzero) digits is 420, while the sum is 21.

The square root of 51123072 is about 7150.0399998881. The cubic root of 51123072 is about 371.1410404771.

Adding to 51123072 its reverse (27032115), we get a palindrome (78155187).

The spelling of 51123072 in words is "fifty-one million, one hundred twenty-three thousand, seventy-two".