158213973661 has 16 divisors (see below), whose sum is σ = 167890240944. Its totient is φ = 148579144704.

The previous prime is 158213973587. The next prime is 158213973677. The reversal of 158213973661 is 166379312851.

158213973661 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 8 ways, for example, as 7922068036 + 150291905625 = 89006^2 + 387675^2 .

It is a cyclic number.

It is not a de Polignac number, because 158213973661 - 2²³ = 158205585053 is a prime.

It is a super-2 number, since 2×158213973661² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 158213973599 and 158213973608.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (158213979661) 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 15 ways as a sum of consecutive naturals, for example, 16250551 + ... + 16260283.

It is an arithmetic number, because the mean of its divisors is an integer number (10493140059).

Almost surely, 2^158213973661 is an apocalyptic number.

It is an amenable number.

158213973661 is a deficient number, since it is larger than the sum of its proper divisors (9676267283).

158213973661 is a wasteful number, since it uses less digits than its factorization.

158213973661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11760.

The product of its digits is 1632960, while the sum is 52.

The spelling of 158213973661 in words is "one hundred fifty-eight billion, two hundred thirteen million, nine hundred seventy-three thousand, six hundred sixty-one".