74820219781 has 4 divisors (see below), whose sum is σ = 74862184672. Its totient is φ = 74778254892.

The previous prime is 74820219763. The next prime is 74820219847. The reversal of 74820219781 is 18791202847.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-74820219781 is a prime.

It is a super-2 number, since 2×74820219781² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (74820219281) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20979771 + ... + 20983336.

It is an arithmetic number, because the mean of its divisors is an integer number (18715546168).

Almost surely, 2^74820219781 is an apocalyptic number.

It is an amenable number.

74820219781 is a deficient number, since it is larger than the sum of its proper divisors (41964891).

74820219781 is a wasteful number, since it uses less digits than its factorization.

74820219781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41964890.

The product of its (nonzero) digits is 451584, while the sum is 49.

The spelling of 74820219781 in words is "seventy-four billion, eight hundred twenty million, two hundred nineteen thousand, seven hundred eighty-one".