28970421 has 16 divisors (see below), whose sum is σ = 40857600. Its totient is φ = 18208368.

The previous prime is 28970419. The next prime is 28970429. The reversal of 28970421 is 12407982.

It is a happy number.

It is not a de Polignac number, because 28970421 - 2¹ = 28970419 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28970429) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11820 + ... + 14058.

It is an arithmetic number, because the mean of its divisors is an integer number (2553600).

Almost surely, 2^28970421 is an apocalyptic number.

It is an amenable number.

28970421 is a deficient number, since it is larger than the sum of its proper divisors (11887179).

28970421 is a wasteful number, since it uses less digits than its factorization.

28970421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2488.

The product of its (nonzero) digits is 8064, while the sum is 33.

The square root of 28970421 is about 5382.4177652798. The cubic root of 28970421 is about 307.1271917942.

The spelling of 28970421 in words is "twenty-eight million, nine hundred seventy thousand, four hundred twenty-one".