51169440 has 192 divisors, whose sum is σ = 187294464. Its totient is φ = 11501568.

The previous prime is 51169397. The next prime is 51169463. The reversal of 51169440 is 4496115.

51169440 = T₁₉₅ + T₁₉₆ + ... + T₆₇₉.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 51169398 and 51169407.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 325842 + ... + 325998.

It is an arithmetic number, because the mean of its divisors is an integer number (975492).

Almost surely, 2^51169440 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 51169440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (93647232).

51169440 is an abundant number, since it is smaller than the sum of its proper divisors (136125024).

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

51169440 is a wasteful number, since it uses less digits than its factorization.

51169440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 279 (or 271 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 30.

The square root of 51169440 is about 7153.2817643373. The cubic root of 51169440 is about 371.2532133631.

The spelling of 51169440 in words is "fifty-one million, one hundred sixty-nine thousand, four hundred forty".