73401578531 has 4 divisors (see below), whose sum is σ = 73402365600. Its totient is φ = 73400791464.

The previous prime is 73401578431. The next prime is 73401578543. The reversal of 73401578531 is 13587510437.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 13587510437 = 79 ⋅171993803.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-73401578531 is a prime.

It is a super-2 number, since 2×73401578531² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (73401578431) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 231371 + ... + 447588.

It is an arithmetic number, because the mean of its divisors is an integer number (18350591400).

Almost surely, 2^73401578531 is an apocalyptic number.

73401578531 is a deficient number, since it is larger than the sum of its proper divisors (787069).

73401578531 is a wasteful number, since it uses less digits than its factorization.

73401578531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 787068.

The product of its (nonzero) digits is 352800, while the sum is 44.

The spelling of 73401578531 in words is "seventy-three billion, four hundred one million, five hundred seventy-eight thousand, five hundred thirty-one".