21036377 has 4 divisors (see below), whose sum is σ = 21332736. Its totient is φ = 20740020.

The previous prime is 21036371. The next prime is 21036409. The reversal of 21036377 is 77363012.

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 21036377 - 2¹⁴ = 21019993 is a prime.

It is a super-2 number, since 2×21036377² = 885058314572258, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21036371) 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, 148073 + ... + 148214.

It is an arithmetic number, because the mean of its divisors is an integer number (5333184).

Almost surely, 2^21036377 is an apocalyptic number.

It is an amenable number.

21036377 is a deficient number, since it is larger than the sum of its proper divisors (296359).

21036377 is an equidigital number, since it uses as much as digits as its factorization.

21036377 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 296358.

The product of its (nonzero) digits is 5292, while the sum is 29.

The square root of 21036377 is about 4586.5430337020. The cubic root of 21036377 is about 276.0516295278.

Adding to 21036377 its reverse (77363012), we get a palindrome (98399389).

The spelling of 21036377 in words is "twenty-one million, thirty-six thousand, three hundred seventy-seven".