21702377 has 4 divisors (see below), whose sum is σ = 21868176. Its totient is φ = 21536580.

The previous prime is 21702371. The next prime is 21702379. The reversal of 21702377 is 77320712.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21702377 - 2⁴ = 21702361 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21702371) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 82703 + ... + 82964.

It is an arithmetic number, because the mean of its divisors is an integer number (5467044).

Almost surely, 2^21702377 is an apocalyptic number.

It is an amenable number.

21702377 is a deficient number, since it is larger than the sum of its proper divisors (165799).

21702377 is a wasteful number, since it uses less digits than its factorization.

21702377 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 165798.

The product of its (nonzero) digits is 4116, while the sum is 29.

The square root of 21702377 is about 4658.5810071308. The cubic root of 21702377 is about 278.9346292378.

The spelling of 21702377 in words is "twenty-one million, seven hundred two thousand, three hundred seventy-seven".