153691961 has 4 divisors (see below), whose sum is σ = 153951732. Its totient is φ = 153432192.

The previous prime is 153691949. The next prime is 153691963. The reversal of 153691961 is 169196351.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 169196351 = 1301 ⋅130051.

It can be written as a sum of positive squares in 2 ways, for example, as 78765625 + 74926336 = 8875^2 + 8656^2 .

It is a cyclic number.

It is not a de Polignac number, because 153691961 - 2⁶ = 153691897 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (153691963) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 128996 + ... + 130181.

It is an arithmetic number, because the mean of its divisors is an integer number (38487933).

Almost surely, 2^153691961 is an apocalyptic number.

It is an amenable number.

153691961 is a deficient number, since it is larger than the sum of its proper divisors (259771).

153691961 is an equidigital number, since it uses as much as digits as its factorization.

153691961 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 259770.

The product of its digits is 43740, while the sum is 41.

The square root of 153691961 is about 12397.2561883668. The cubic root of 153691961 is about 535.6532167356.

The spelling of 153691961 in words is "one hundred fifty-three million, six hundred ninety-one thousand, nine hundred sixty-one".