21140677 has 2 divisors, whose sum is σ = 21140678. Its totient is φ = 21140676.

The previous prime is 21140663. The next prime is 21140683. The reversal of 21140677 is 77604112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14333796 + 6806881 = 3786^2 + 2609^2 .

It is a cyclic number.

It is not a de Polignac number, because 21140677 - 2⁷ = 21140549 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21140377) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10570338 + 10570339.

It is an arithmetic number, because the mean of its divisors is an integer number (10570339).

Almost surely, 2^21140677 is an apocalyptic number.

It is an amenable number.

21140677 is a deficient number, since it is larger than the sum of its proper divisors (1).

21140677 is an equidigital number, since it uses as much as digits as its factorization.

21140677 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2352, while the sum is 28.

The square root of 21140677 is about 4597.8991941973. The cubic root of 21140677 is about 276.5071061048.

Adding to 21140677 its reverse (77604112), we get a palindrome (98744789).

The spelling of 21140677 in words is "twenty-one million, one hundred forty thousand, six hundred seventy-seven".