51421755 has 48 divisors (see below), whose sum is σ = 103064832. Its totient is φ = 21268800.

The previous prime is 51421751. The next prime is 51421757. The reversal of 51421755 is 55712415.

It is not a de Polignac number, because 51421755 - 2² = 51421751 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51421751) 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 47 ways as a sum of consecutive naturals, for example, 243600 + ... + 243810.

It is an arithmetic number, because the mean of its divisors is an integer number (2147184).

Almost surely, 2^51421755 is an apocalyptic number.

51421755 is a gapful number since it is divisible by the number (55) formed by its first and last digit.

51421755 is an abundant number, since it is smaller than the sum of its proper divisors (51643077).

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

51421755 is a wasteful number, since it uses less digits than its factorization.

51421755 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 448 (or 237 counting only the distinct ones).

The product of its digits is 7000, while the sum is 30.

The square root of 51421755 is about 7170.8963874818. The cubic root of 51421755 is about 371.8624260042.

The spelling of 51421755 in words is "fifty-one million, four hundred twenty-one thousand, seven hundred fifty-five".