21112977 has 8 divisors (see below), whose sum is σ = 28911616. Its totient is φ = 13694832.

The previous prime is 21112969. The next prime is 21112979. The reversal of 21112977 is 77921112.

It is a happy number.

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

It is not a de Polignac number, because 21112977 - 2³ = 21112969 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21112979) 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, 94993 + ... + 95214.

It is an arithmetic number, because the mean of its divisors is an integer number (3613952).

Almost surely, 2^21112977 is an apocalyptic number.

It is an amenable number.

21112977 is a deficient number, since it is larger than the sum of its proper divisors (7798639).

21112977 is a wasteful number, since it uses less digits than its factorization.

21112977 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 190247.

The product of its digits is 1764, while the sum is 30.

The square root of 21112977 is about 4594.8859615882. The cubic root of 21112977 is about 276.3862869765.

The spelling of 21112977 in words is "twenty-one million, one hundred twelve thousand, nine hundred seventy-seven".