51551001 has 6 divisors (see below), whose sum is σ = 74462570. Its totient is φ = 34367328.

The previous prime is 51550999. The next prime is 51551077. The reversal of 51551001 is 10015515.

It can be written as a sum of positive squares in only one way, i.e., 35390601 + 16160400 = 5949^2 + 4020^2 .

It is not a de Polignac number, because 51551001 - 2¹ = 51550999 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51551081) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2863936 + ... + 2863953.

Almost surely, 2^51551001 is an apocalyptic number.

It is an amenable number.

51551001 is a deficient number, since it is larger than the sum of its proper divisors (22911569).

51551001 is a wasteful number, since it uses less digits than its factorization.

51551001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5727895 (or 5727892 counting only the distinct ones).

The product of its (nonzero) digits is 125, while the sum is 18.

The square root of 51551001 is about 7179.9025759407. The cubic root of 51551001 is about 372.1737178581.

Adding to 51551001 its reverse (10015515), we get a palindrome (61566516).

The spelling of 51551001 in words is "fifty-one million, five hundred fifty-one thousand, one".