1958406423921 has 24 divisors (see below), whose sum is σ = 2899406914560. Its totient is φ = 1273369247136.

The previous prime is 1958406423851. The next prime is 1958406423973. The reversal of 1958406423921 is 1293246048591.

It is a happy number.

1958406423921 is a `hidden beast` number, since 1 + 9 + 584 + 0 + 6 + 4 + 2 + 39 + 21 = 666.

It is not a de Polignac number, because 1958406423921 - 2¹⁷ = 1958406292849 is a prime.

It is a super-2 number, since 2×1958406423921² (a number of 25 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1958406423121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 14452830 + ... + 14587703.

It is an arithmetic number, because the mean of its divisors is an integer number (120808621440).

Almost surely, 2^{1958406423921} is an apocalyptic number.

It is an amenable number.

1958406423921 is a deficient number, since it is larger than the sum of its proper divisors (941000490639).

1958406423921 is a wasteful number, since it uses less digits than its factorization.

1958406423921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29040725 (or 29040722 counting only the distinct ones).

The product of its (nonzero) digits is 3732480, while the sum is 54.

The spelling of 1958406423921 in words is "one trillion, nine hundred fifty-eight billion, four hundred six million, four hundred twenty-three thousand, nine hundred twenty-one".