185421819399 has 12 divisors (see below), whose sum is σ = 262627445544. Its totient is φ = 116343101824.

The previous prime is 185421819361. The next prime is 185421819437. The reversal of 185421819399 is 993918124581.

It is an interprime number because it is at equal distance from previous prime (185421819361) and next prime (185421819437).

It is not a de Polignac number, because 185421819399 - 2¹³ = 185421811207 is a prime.

It is a super-2 number, since 2×185421819399² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (185421812399) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 106932132 + ... + 106933865.

It is an arithmetic number, because the mean of its divisors is an integer number (21885620462).

Almost surely, 2^185421819399 is an apocalyptic number.

185421819399 is a deficient number, since it is larger than the sum of its proper divisors (77205626145).

185421819399 is a wasteful number, since it uses less digits than its factorization.

185421819399 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 213866034 (or 213866017 counting only the distinct ones).

The product of its digits is 5598720, while the sum is 60.

The spelling of 185421819399 in words is "one hundred eighty-five billion, four hundred twenty-one million, eight hundred nineteen thousand, three hundred ninety-nine".