90432421 has 8 divisors (see below), whose sum is σ = 91992600. Its totient is φ = 88885248.

The previous prime is 90432383. The next prime is 90432437. The reversal of 90432421 is 12423409.

It can be written as a sum of positive squares in 4 ways, for example, as 20124196 + 70308225 = 4486^2 + 8385^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 90432421 - 2⁹ = 90431909 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (90432451) 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, 11325 + ... + 17581.

It is an arithmetic number, because the mean of its divisors is an integer number (11499075).

Almost surely, 2^90432421 is an apocalyptic number.

It is an amenable number.

90432421 is a deficient number, since it is larger than the sum of its proper divisors (1560179).

90432421 is a wasteful number, since it uses less digits than its factorization.

90432421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6503.

The product of its (nonzero) digits is 1728, while the sum is 25.

The square root of 90432421 is about 9509.5962585170. The cubic root of 90432421 is about 448.8570517641.

The spelling of 90432421 in words is "ninety million, four hundred thirty-two thousand, four hundred twenty-one".