167651481406421 has 4 divisors (see below), whose sum is σ = 167652766744512. Its totient is φ = 167650196068332.

The previous prime is 167651481406393. The next prime is 167651481406433. The reversal of 167651481406421 is 124604184156761.

It is a happy number.

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 not a de Polignac number, because 167651481406421 - 2²⁶ = 167651414297557 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (167651481400421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 642473375 + ... + 642734268.

It is an arithmetic number, because the mean of its divisors is an integer number (41913191686128).

Almost surely, 2^{167651481406421} is an apocalyptic number.

It is an amenable number.

167651481406421 is a deficient number, since it is larger than the sum of its proper divisors (1285338091).

167651481406421 is a wasteful number, since it uses less digits than its factorization.

167651481406421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1285338090.

The product of its (nonzero) digits is 7741440, while the sum is 56.

The spelling of 167651481406421 in words is "one hundred sixty-seven trillion, six hundred fifty-one billion, four hundred eighty-one million, four hundred six thousand, four hundred twenty-one".