181409401958381 has 2 divisors, whose sum is σ = 181409401958382. Its totient is φ = 181409401958380.

The previous prime is 181409401958353. The next prime is 181409401958423. The reversal of 181409401958381 is 183859104904181.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 107680904517481 + 73728497440900 = 10376941^2 + 8586530^2 .

It is a cyclic number.

It is not a de Polignac number, because 181409401958381 - 2¹⁴ = 181409401941997 is a prime.

It is a super-2 number, since 2×181409401958381² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (181409401954381) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 90704700979190 + 90704700979191.

It is an arithmetic number, because the mean of its divisors is an integer number (90704700979191).

Almost surely, 2^{181409401958381} is an apocalyptic number.

It is an amenable number.

181409401958381 is a deficient number, since it is larger than the sum of its proper divisors (1).

181409401958381 is an equidigital number, since it uses as much as digits as its factorization.

181409401958381 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 9953280, while the sum is 62.

The spelling of 181409401958381 in words is "one hundred eighty-one trillion, four hundred nine billion, four hundred one million, nine hundred fifty-eight thousand, three hundred eighty-one".