21928377 has 8 divisors (see below), whose sum is σ = 30181120. Its totient is φ = 14147280.

The previous prime is 21928343. The next prime is 21928381. The reversal of 21928377 is 77382912.

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

It is not a de Polignac number, because 21928377 - 2⁸ = 21928121 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21928327) 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, 117802 + ... + 117987.

It is an arithmetic number, because the mean of its divisors is an integer number (3772640).

Almost surely, 2^21928377 is an apocalyptic number.

It is an amenable number.

21928377 is a deficient number, since it is larger than the sum of its proper divisors (8252743).

21928377 is a wasteful number, since it uses less digits than its factorization.

21928377 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 235823.

The product of its digits is 42336, while the sum is 39.

The square root of 21928377 is about 4682.7744980941. The cubic root of 21928377 is about 279.8995260255.

The spelling of 21928377 in words is "twenty-one million, nine hundred twenty-eight thousand, three hundred seventy-seven".