51435231491 has 16 divisors (see below), whose sum is σ = 59237256960. Its totient is φ = 43748052000.

The previous prime is 51435231487. The next prime is 51435231511. The reversal of 51435231491 is 19413253415.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 51435231491 - 2² = 51435231487 is a prime.

It is not an unprimeable number, because it can be changed into a prime (51435231391) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 418220 + ... + 527046.

It is an arithmetic number, because the mean of its divisors is an integer number (3702328560).

Almost surely, 2^51435231491 is an apocalyptic number.

51435231491 is a deficient number, since it is larger than the sum of its proper divisors (7802025469).

51435231491 is a wasteful number, since it uses less digits than its factorization.

51435231491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 109354.

The product of its digits is 64800, while the sum is 38.

The spelling of 51435231491 in words is "fifty-one billion, four hundred thirty-five million, two hundred thirty-one thousand, four hundred ninety-one".