51240280 has 96 divisors (see below), whose sum is σ = 144501840. Its totient is φ = 16208640.

The previous prime is 51240253. The next prime is 51240307. The reversal of 51240280 is 8204215.

It is an interprime number because it is at equal distance from previous prime (51240253) and next prime (51240307).

It is a hoax number, since the sum of its digits (22) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 24475 + ... + 26485.

Almost surely, 2^51240280 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 51240280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (72250920).

51240280 is an abundant number, since it is smaller than the sum of its proper divisors (93261560).

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

51240280 is a wasteful number, since it uses less digits than its factorization.

51240280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2049 (or 2038 counting only the distinct ones).

The product of its (nonzero) digits is 640, while the sum is 22.

The square root of 51240280 is about 7158.2316251991. The cubic root of 51240280 is about 371.4244578299.

Adding to 51240280 its reverse (8204215), we get a palindrome (59444495).

The spelling of 51240280 in words is "fifty-one million, two hundred forty thousand, two hundred eighty".