21187077 has 8 divisors (see below), whose sum is σ = 28728480. Its totient is φ = 13885200.

The previous prime is 21187063. The next prime is 21187079. The reversal of 21187077 is 77078112.

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

It is not a de Polignac number, because 21187077 - 2⁶ = 21187013 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21187079) 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, 59674 + ... + 60027.

It is an arithmetic number, because the mean of its divisors is an integer number (3591060).

Almost surely, 2^21187077 is an apocalyptic number.

It is an amenable number.

21187077 is a deficient number, since it is larger than the sum of its proper divisors (7541403).

21187077 is a wasteful number, since it uses less digits than its factorization.

21187077 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 119763.

The product of its (nonzero) digits is 5488, while the sum is 33.

The square root of 21187077 is about 4602.9422112384. The cubic root of 21187077 is about 276.7092528113.

The spelling of 21187077 in words is "twenty-one million, one hundred eighty-seven thousand, seventy-seven".