51539077949 has 4 divisors (see below), whose sum is σ = 52511513436. Its totient is φ = 50566642464.

The previous prime is 51539077943. The next prime is 51539077951. The reversal of 51539077949 is 94977093515.

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

It can be written as a sum of positive squares in 2 ways, for example, as 39332805625 + 12206272324 = 198325^2 + 110482^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51539077949 is a prime.

It is a super-3 number, since 3×51539077949³ (a number of 33 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51539077943) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 486217664 + ... + 486217769.

It is an arithmetic number, because the mean of its divisors is an integer number (13127878359).

Almost surely, 2^51539077949 is an apocalyptic number.

It is an amenable number.

51539077949 is a deficient number, since it is larger than the sum of its proper divisors (972435487).

51539077949 is an equidigital number, since it uses as much as digits as its factorization.

51539077949 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 972435486.

The product of its (nonzero) digits is 10716300, while the sum is 59.

The spelling of 51539077949 in words is "fifty-one billion, five hundred thirty-nine million, seventy-seven thousand, nine hundred forty-nine".