154240421 has 2 divisors, whose sum is σ = 154240422. Its totient is φ = 154240420.

The previous prime is 154240409. The next prime is 154240447. The reversal of 154240421 is 124042451.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 130279396 + 23961025 = 11414^2 + 4895^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-154240421 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (154240481) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 77120210 + 77120211.

It is an arithmetic number, because the mean of its divisors is an integer number (77120211).

Almost surely, 2^154240421 is an apocalyptic number.

It is an amenable number.

154240421 is a deficient number, since it is larger than the sum of its proper divisors (1).

154240421 is an equidigital number, since it uses as much as digits as its factorization.

154240421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1280, while the sum is 23.

The square root of 154240421 is about 12419.3567063677. The cubic root of 154240421 is about 536.2896316995.

Adding to 154240421 its reverse (124042451), we get a palindrome (278282872).

The spelling of 154240421 in words is "one hundred fifty-four million, two hundred forty thousand, four hundred twenty-one".