21872377 has 2 divisors, whose sum is σ = 21872378. Its totient is φ = 21872376.

The previous prime is 21872371. The next prime is 21872399. The reversal of 21872377 is 77327812.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21724921 + 147456 = 4661^2 + 384^2 .

It is a cyclic number.

It is not a de Polignac number, because 21872377 - 2³ = 21872369 is a prime.

It is not a weakly prime, because it can be changed into another prime (21872371) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10936188 + 10936189.

It is an arithmetic number, because the mean of its divisors is an integer number (10936189).

Almost surely, 2^21872377 is an apocalyptic number.

It is an amenable number.

21872377 is a deficient number, since it is larger than the sum of its proper divisors (1).

21872377 is an equidigital number, since it uses as much as digits as its factorization.

21872377 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 32928, while the sum is 37.

The square root of 21872377 is about 4676.7913145660. The cubic root of 21872377 is about 279.6610567074.

The spelling of 21872377 in words is "twenty-one million, eight hundred seventy-two thousand, three hundred seventy-seven".