28621867 has 4 divisors (see below), whose sum is σ = 29866320. Its totient is φ = 27377416.

The previous prime is 28621861. The next prime is 28621877. The reversal of 28621867 is 76812682.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28621867 is a prime.

It is a super-2 number, since 2×28621867² = 1638422541131378, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28621861) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 622192 + ... + 622237.

It is an arithmetic number, because the mean of its divisors is an integer number (7466580).

Almost surely, 2^28621867 is an apocalyptic number.

28621867 is a deficient number, since it is larger than the sum of its proper divisors (1244453).

28621867 is a wasteful number, since it uses less digits than its factorization.

28621867 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1244452.

The product of its digits is 64512, while the sum is 40.

The square root of 28621867 is about 5349.9408407944. The cubic root of 28621867 is about 305.8904979347.

The spelling of 28621867 in words is "twenty-eight million, six hundred twenty-one thousand, eight hundred sixty-seven".