51665426 has 4 divisors (see below), whose sum is σ = 77498142. Its totient is φ = 25832712.

The previous prime is 51665423. The next prime is 51665461. The reversal of 51665426 is 62456615.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 45900625 + 5764801 = 6775^2 + 2401^2 .

It is a super-2 number, since 2×51665426² = 5338632487522952, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (51665423) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12916355 + ... + 12916358.

Almost surely, 2^51665426 is an apocalyptic number.

51665426 is a deficient number, since it is larger than the sum of its proper divisors (25832716).

51665426 is a wasteful number, since it uses less digits than its factorization.

51665426 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25832715.

The product of its digits is 43200, while the sum is 35.

The square root of 51665426 is about 7187.8665819560. The cubic root of 51665426 is about 372.4488790708.

The spelling of 51665426 in words is "fifty-one million, six hundred sixty-five thousand, four hundred twenty-six".