51481404 has 72 divisors (see below), whose sum is σ = 143615472. Its totient is φ = 15448320.

The previous prime is 51481369. The next prime is 51481439. The reversal of 51481404 is 40418415.

It is a happy number.

51481404 is a `hidden beast` number, since 514 + 8 + 140 + 4 = 666.

It is an interprime number because it is at equal distance from previous prime (51481369) and next prime (51481439).

It is a super-2 number, since 2×51481404² = 5300669915622432, which contains 22 as substring.

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, 17847 + ... + 20529.

Almost surely, 2^51481404 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 51481404, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (71807736).

51481404 is an abundant number, since it is smaller than the sum of its proper divisors (92134068).

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

51481404 is a wasteful number, since it uses less digits than its factorization.

51481404 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2747 (or 2742 counting only the distinct ones).

The product of its (nonzero) digits is 2560, while the sum is 27.

The square root of 51481404 is about 7175.0542855089. The cubic root of 51481404 is about 372.0061566792.

Adding to 51481404 its reverse (40418415), we get a palindrome (91899819).

It can be divided in two parts, 514 and 81404, that added together give a palindrome (81918).

The spelling of 51481404 in words is "fifty-one million, four hundred eighty-one thousand, four hundred four".