51121845 has 12 divisors (see below), whose sum is σ = 88611276. Its totient is φ = 27264960.

The previous prime is 51121841. The next prime is 51121849. The reversal of 51121845 is 54812115.

It is an interprime number because it is at equal distance from previous prime (51121841) and next prime (51121849).

It can be written as a sum of positive squares in 2 ways, for example, as 13593969 + 37527876 = 3687^2 + 6126^2 .

It is not a de Polignac number, because 51121845 - 2² = 51121841 is a prime.

It is a super-2 number, since 2×51121845² = 5226886072408050, which contains 22 as substring.

It is a Smith number, since the sum of its digits (27) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51121841) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 567976 + ... + 568065.

It is an arithmetic number, because the mean of its divisors is an integer number (7384273).

Almost surely, 2^51121845 is an apocalyptic number.

It is an amenable number.

51121845 is a deficient number, since it is larger than the sum of its proper divisors (37489431).

51121845 is a wasteful number, since it uses less digits than its factorization.

51121845 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1136052 (or 1136049 counting only the distinct ones).

The product of its digits is 1600, while the sum is 27.

The square root of 51121845 is about 7149.9541956575. The cubic root of 51121845 is about 371.1380712131.

The spelling of 51121845 in words is "fifty-one million, one hundred twenty-one thousand, eight hundred forty-five".