51243536461645 has 32 divisors (see below), whose sum is σ = 68178138742656. Its totient is φ = 36664009824000.

The previous prime is 51243536461639. The next prime is 51243536461669. The reversal of 51243536461645 is 54616463534215.

It is not a de Polignac number, because 51243536461645 - 2¹¹ = 51243536459597 is a prime.

It is a super-3 number, since 3×51243536461645³ (a number of 42 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Harshad number since it is a multiple of its sum of digits (55).

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 28506079 + ... + 30250348.

It is an arithmetic number, because the mean of its divisors is an integer number (2130566835708).

Almost surely, 2^{51243536461645} is an apocalyptic number.

51243536461645 is a gapful number since it is divisible by the number (55) formed by its first and last digit.

It is an amenable number.

51243536461645 is a deficient number, since it is larger than the sum of its proper divisors (16934602281011).

51243536461645 is a wasteful number, since it uses less digits than its factorization.

51243536461645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 58756701.

The product of its digits is 31104000, while the sum is 55.

The spelling of 51243536461645 in words is "fifty-one trillion, two hundred forty-three billion, five hundred thirty-six million, four hundred sixty-one thousand, six hundred forty-five".