51690655 has 4 divisors (see below), whose sum is σ = 62028792. Its totient is φ = 41352520.

The previous prime is 51690649. The next prime is 51690677. The reversal of 51690655 is 55609615.

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

It is not a de Polignac number, because 51690655 - 2⁵ = 51690623 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5169061 + ... + 5169070.

It is an arithmetic number, because the mean of its divisors is an integer number (15507198).

Almost surely, 2^51690655 is an apocalyptic number.

51690655 is a deficient number, since it is larger than the sum of its proper divisors (10338137).

51690655 is a wasteful number, since it uses less digits than its factorization.

51690655 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10338136.

The product of its (nonzero) digits is 40500, while the sum is 37.

The square root of 51690655 is about 7189.6213391249. The cubic root of 51690655 is about 372.5094933244.

It can be divided in two parts, 516906 and 55, that added together give a square (516961 = 719²).

The spelling of 51690655 in words is "fifty-one million, six hundred ninety thousand, six hundred fifty-five".