145686821 has 8 divisors (see below), whose sum is σ = 176293440. Its totient is φ = 117528768.

The previous prime is 145686811. The next prime is 145686833. The reversal of 145686821 is 128686541.

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

It is not a de Polignac number, because 145686821 - 2¹⁰ = 145685797 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 (145686811) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 612011 + ... + 612248.

It is an arithmetic number, because the mean of its divisors is an integer number (22036680).

Almost surely, 2^145686821 is an apocalyptic number.

It is an amenable number.

145686821 is a deficient number, since it is larger than the sum of its proper divisors (30606619).

145686821 is a wasteful number, since it uses less digits than its factorization.

145686821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1224283.

The product of its digits is 92160, while the sum is 41.

The square root of 145686821 is about 12070.0795772025. The cubic root of 145686821 is about 526.1869693919.

The spelling of 145686821 in words is "one hundred forty-five million, six hundred eighty-six thousand, eight hundred twenty-one".