51261554 has 4 divisors (see below), whose sum is σ = 76892334. Its totient is φ = 25630776.

The previous prime is 51261541. The next prime is 51261557. The reversal of 51261554 is 45516215.

It is a happy number.

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

It can be written as a sum of positive squares in only one way, i.e., 33814225 + 17447329 = 5815^2 + 4177^2 .

It is not an unprimeable number, because it can be changed into a prime (51261557) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12815387 + ... + 12815390.

Almost surely, 2^51261554 is an apocalyptic number.

51261554 is a deficient number, since it is larger than the sum of its proper divisors (25630780).

51261554 is a wasteful number, since it uses less digits than its factorization.

51261554 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25630779.

The product of its digits is 6000, while the sum is 29.

The square root of 51261554 is about 7159.7174525256. The cubic root of 51261554 is about 371.4758535328.

Adding to 51261554 its reverse (45516215), we get a palindrome (96777769).

It can be divided in two parts, 51261 and 554, that added together give a palindrome (51815).

The spelling of 51261554 in words is "fifty-one million, two hundred sixty-one thousand, five hundred fifty-four".