43194516981 has 16 divisors (see below), whose sum is σ = 71803872768. Its totient is φ = 22438710000.

The previous prime is 43194516977. The next prime is 43194516983. The reversal of 43194516981 is 18961549134.

It is a happy number.

It is not a de Polignac number, because 43194516981 - 2² = 43194516977 is a prime.

It is a super-2 number, since 2×43194516981² (a number of 22 digits) contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (43194516983) 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, 93494395 + ... + 93494856.

It is an arithmetic number, because the mean of its divisors is an integer number (4487742048).

Almost surely, 2^43194516981 is an apocalyptic number.

It is an amenable number.

43194516981 is a deficient number, since it is larger than the sum of its proper divisors (28609355787).

43194516981 is a wasteful number, since it uses less digits than its factorization.

43194516981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 186989272.

The product of its digits is 933120, while the sum is 51.

The spelling of 43194516981 in words is "forty-three billion, one hundred ninety-four million, five hundred sixteen thousand, nine hundred eighty-one".