51206401 has 4 divisors (see below), whose sum is σ = 51224404. Its totient is φ = 51188400.

The previous prime is 51206377. The next prime is 51206413. The reversal of 51206401 is 10460215.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 10460215 = 5 ⋅2092043.

It can be written as a sum of positive squares in 2 ways, for example, as 10246401 + 40960000 = 3201^2 + 6400^2 .

It is a cyclic number.

It is not a de Polignac number, because 51206401 - 2¹¹ = 51204353 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51206471) 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, 3690 + ... + 10771.

It is an arithmetic number, because the mean of its divisors is an integer number (12806101).

Almost surely, 2^51206401 is an apocalyptic number.

It is an amenable number.

51206401 is a deficient number, since it is larger than the sum of its proper divisors (18003).

51206401 is a wasteful number, since it uses less digits than its factorization.

51206401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18002.

The product of its (nonzero) digits is 240, while the sum is 19.

The square root of 51206401 is about 7155.8647974930. The cubic root of 51206401 is about 371.3425804245.

Adding to 51206401 its reverse (10460215), we get a palindrome (61666616).

The spelling of 51206401 in words is "fifty-one million, two hundred six thousand, four hundred one".