51266440 has 64 divisors (see below), whose sum is σ = 118787760. Its totient is φ = 19906560.

The previous prime is 51266437. The next prime is 51266477. The reversal of 51266440 is 4466215.

It can be written as a sum of positive squares in 8 ways, for example, as 7150276 + 44116164 = 2674^2 + 6642^2 .

It is a junction number, because it is equal to n+sod(n) for n = 51266399 and 51266408.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 283150 + ... + 283330.

Almost surely, 2^51266440 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 51266440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (59393880).

51266440 is an abundant number, since it is smaller than the sum of its proper divisors (67521320).

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

51266440 is a wasteful number, since it uses less digits than its factorization.

51266440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 362 (or 358 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 28.

The square root of 51266440 is about 7160.0586589776. The cubic root of 51266440 is about 371.4876555769.

The spelling of 51266440 in words is "fifty-one million, two hundred sixty-six thousand, four hundred forty".