51201997 has 24 divisors (see below), whose sum is σ = 65440256. Its totient is φ = 39204000.

The previous prime is 51201991. The next prime is 51202007. The reversal of 51201997 is 79910215.

It is not a de Polignac number, because 51201997 - 2¹⁹ = 50677709 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51201991) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 51172 + ... + 52162.

Almost surely, 2^51201997 is an apocalyptic number.

It is an amenable number.

51201997 is a deficient number, since it is larger than the sum of its proper divisors (14238259).

51201997 is a wasteful number, since it uses less digits than its factorization.

51201997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1081 (or 1070 counting only the distinct ones).

The product of its (nonzero) digits is 5670, while the sum is 34.

The square root of 51201997 is about 7155.5570712559. The cubic root of 51201997 is about 371.3319343621.

It can be divided in two parts, 5120 and 1997, that added together give a palindrome (7117).

The spelling of 51201997 in words is "fifty-one million, two hundred one thousand, nine hundred ninety-seven".