51155666 has 16 divisors (see below), whose sum is σ = 77828856. Its totient is φ = 25214976.

The previous prime is 51155641. The next prime is 51155677. The reversal of 51155666 is 66655115.

It can be written as a sum of positive squares in 4 ways, for example, as 50197225 + 958441 = 7085^2 + 979^2 .

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 88370 + ... + 88946.

Almost surely, 2^51155666 is an apocalyptic number.

51155666 is a deficient number, since it is larger than the sum of its proper divisors (26673190).

51155666 is a wasteful number, since it uses less digits than its factorization.

51155666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1133.

The product of its digits is 27000, while the sum is 35.

The square root of 51155666 is about 7152.3189246565. The cubic root of 51155666 is about 371.2198985521.

The spelling of 51155666 in words is "fifty-one million, one hundred fifty-five thousand, six hundred sixty-six".