21396376 has 8 divisors (see below), whose sum is σ = 40118220. Its totient is φ = 10698184.

The previous prime is 21396317. The next prime is 21396379. The reversal of 21396376 is 67369312.

It is a tau number, because it is divible by the number of its divisors (8).

It is a hoax number, since the sum of its digits (37) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21396379) 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 as a sum of consecutive naturals, namely, 1337266 + ... + 1337281.

Almost surely, 2^21396376 is an apocalyptic number.

21396376 is the 2926-th centered pentagonal number.

It is an amenable number.

21396376 is a deficient number, since it is larger than the sum of its proper divisors (18721844).

21396376 is a wasteful number, since it uses less digits than its factorization.

21396376 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2674553 (or 2674549 counting only the distinct ones).

The product of its digits is 40824, while the sum is 37.

The square root of 21396376 is about 4625.6216879464. The cubic root of 21396376 is about 277.6174369700.

It can be divided in two parts, 2139 and 6376, that added together give a triangular number (8515 = T₁₃₀).

The spelling of 21396376 in words is "twenty-one million, three hundred ninety-six thousand, three hundred seventy-six".