51157706 has 4 divisors (see below), whose sum is σ = 76736562. Its totient is φ = 25578852.

The previous prime is 51157697. The next prime is 51157739. The reversal of 51157706 is 60775115.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 60775115 = 5 ⋅12155023.

It can be written as a sum of positive squares in only one way, i.e., 46117681 + 5040025 = 6791^2 + 2245^2 .

It is a super-2 number, since 2×51157706² = 5234221766364872, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12789425 + ... + 12789428.

Almost surely, 2^51157706 is an apocalyptic number.

51157706 is a deficient number, since it is larger than the sum of its proper divisors (25578856).

51157706 is a wasteful number, since it uses less digits than its factorization.

51157706 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25578855.

The product of its (nonzero) digits is 7350, while the sum is 32.

The square root of 51157706 is about 7152.4615343251. The cubic root of 51157706 is about 371.2248330236.

It can be divided in two parts, 5115 and 7706, that added together give a palindrome (12821).

The spelling of 51157706 in words is "fifty-one million, one hundred fifty-seven thousand, seven hundred six".