51511690 has 8 divisors (see below), whose sum is σ = 92721060. Its totient is φ = 20604672.

The previous prime is 51511657. The next prime is 51511693. The reversal of 51511690 is 9611515.

It can be written as a sum of positive squares in 2 ways, for example, as 49829481 + 1682209 = 7059^2 + 1297^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×51511690² = 5306908413312200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (51511693) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2575575 + ... + 2575594.

Almost surely, 2^51511690 is an apocalyptic number.

51511690 is a deficient number, since it is larger than the sum of its proper divisors (41209370).

51511690 is a wasteful number, since it uses less digits than its factorization.

51511690 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5151176.

The product of its (nonzero) digits is 1350, while the sum is 28.

The square root of 51511690 is about 7177.1644818828. The cubic root of 51511690 is about 372.0790915578.

The spelling of 51511690 in words is "fifty-one million, five hundred eleven thousand, six hundred ninety".