136231921 has 8 divisors (see below), whose sum is σ = 162463104. Its totient is φ = 111693120.

The previous prime is 136231877. The next prime is 136231981. The reversal of 136231921 is 129132631.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 136231921 - 2⁷ = 136231793 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 136231921.

It is not an unprimeable number, because it can be changed into a prime (136231981) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 422920 + ... + 423241.

It is an arithmetic number, because the mean of its divisors is an integer number (20307888).

Almost surely, 2^136231921 is an apocalyptic number.

It is an amenable number.

136231921 is a deficient number, since it is larger than the sum of its proper divisors (26231183).

136231921 is an equidigital number, since it uses as much as digits as its factorization.

136231921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 846191.

The product of its digits is 1944, while the sum is 28.

The square root of 136231921 is about 11671.8430849631. The cubic root of 136231921 is about 514.5484728091.

The spelling of 136231921 in words is "one hundred thirty-six million, two hundred thirty-one thousand, nine hundred twenty-one".