154149821 has 4 divisors (see below), whose sum is σ = 176171232. Its totient is φ = 132128412.

The previous prime is 154149803. The next prime is 154149839. The reversal of 154149821 is 128941451.

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 an interprime number because it is at equal distance from previous prime (154149803) and next prime (154149839).

It is a cyclic number.

It is not a de Polignac number, because 154149821 - 2²² = 149955517 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (154149221) 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, 11010695 + ... + 11010708.

It is an arithmetic number, because the mean of its divisors is an integer number (44042808).

Almost surely, 2^154149821 is an apocalyptic number.

It is an amenable number.

154149821 is a deficient number, since it is larger than the sum of its proper divisors (22021411).

154149821 is an equidigital number, since it uses as much as digits as its factorization.

154149821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22021410.

The product of its digits is 11520, while the sum is 35.

The square root of 154149821 is about 12415.7086386561. The cubic root of 154149821 is about 536.1846065773.

The spelling of 154149821 in words is "one hundred fifty-four million, one hundred forty-nine thousand, eight hundred twenty-one".