51161787 has 40 divisors (see below), whose sum is σ = 80520176. Its totient is φ = 32332608.

The previous prime is 51161783. The next prime is 51161797. The reversal of 51161787 is 78716115.

It is a happy number.

51161787 is a `hidden beast` number, since 511 + 61 + 7 + 87 = 666.

It is not a de Polignac number, because 51161787 - 2² = 51161783 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51161783) 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, 128673 + ... + 129069.

Almost surely, 2^51161787 is an apocalyptic number.

51161787 is a deficient number, since it is larger than the sum of its proper divisors (29358389).

51161787 is a wasteful number, since it uses less digits than its factorization.

51161787 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 489 (or 480 counting only the distinct ones).

The product of its digits is 11760, while the sum is 36.

The square root of 51161787 is about 7152.7468150355. The cubic root of 51161787 is about 371.2347039918.

It can be divided in two parts, 5116 and 1787, that added together give a triangular number (6903 = T₁₁₇).

The spelling of 51161787 in words is "fifty-one million, one hundred sixty-one thousand, seven hundred eighty-seven".