43521387345 has 32 divisors (see below), whose sum is σ = 77695142400. Its totient is φ = 23114270592.

The previous prime is 43521387337. The next prime is 43521387367. The reversal of 43521387345 is 54378312534.

43521387345 is a `hidden beast` number, since 4 + 3 + 521 + 3 + 87 + 3 + 45 = 666.

It is not a de Polignac number, because 43521387345 - 2³ = 43521387337 is a prime.

It is a super-2 number, since 2×43521387345² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 43521387345.

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, 642172 + ... + 706701.

It is an arithmetic number, because the mean of its divisors is an integer number (2427973200).

Almost surely, 2^43521387345 is an apocalyptic number.

43521387345 is a gapful number since it is divisible by the number (45) formed by its first and last digit.

It is an amenable number.

43521387345 is a deficient number, since it is larger than the sum of its proper divisors (34173755055).

43521387345 is a wasteful number, since it uses less digits than its factorization.

43521387345 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1349126 (or 1349120 counting only the distinct ones).

The product of its digits is 1209600, while the sum is 45.

Adding to 43521387345 its reverse (54378312534), we get a palindrome (97899699879).

The spelling of 43521387345 in words is "forty-three billion, five hundred twenty-one million, three hundred eighty-seven thousand, three hundred forty-five".