51771555 has 40 divisors (see below), whose sum is σ = 101250864. Its totient is φ = 25099200.

The previous prime is 51771553. The next prime is 51771557. The reversal of 51771555 is 55517715.

It is an interprime number because it is at equal distance from previous prime (51771553) and next prime (51771557).

It is not a de Polignac number, because 51771555 - 2¹ = 51771553 is a prime.

It is not an unprimeable number, because it can be changed into a prime (51771553) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 1356 + ... + 10265.

Almost surely, 2^51771555 is an apocalyptic number.

51771555 is a gapful number since it is divisible by the number (55) formed by its first and last digit.

51771555 is a deficient number, since it is larger than the sum of its proper divisors (49479309).

51771555 is a wasteful number, since it uses less digits than its factorization.

51771555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11649 (or 11640 counting only the distinct ones).

The product of its digits is 30625, while the sum is 36.

The square root of 51771555 is about 7195.2453050608. The cubic root of 51771555 is about 372.7037277233.

It can be divided in two parts, 51771 and 555, that added together give a triangular number (52326 = T₃₂₃).

The spelling of 51771555 in words is "fifty-one million, seven hundred seventy-one thousand, five hundred fifty-five".