21314857 has 2 divisors, whose sum is σ = 21314858. Its totient is φ = 21314856.

The previous prime is 21314837. The next prime is 21314861. The reversal of 21314857 is 75841312.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20602521 + 712336 = 4539^2 + 844^2 .

It is a cyclic number.

It is not a de Polignac number, because 21314857 - 2⁷ = 21314729 is a prime.

It is not a weakly prime, because it can be changed into another prime (21314837) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10657428 + 10657429.

It is an arithmetic number, because the mean of its divisors is an integer number (10657429).

Almost surely, 2^21314857 is an apocalyptic number.

It is an amenable number.

21314857 is a deficient number, since it is larger than the sum of its proper divisors (1).

21314857 is an equidigital number, since it uses as much as digits as its factorization.

21314857 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6720, while the sum is 31.

The square root of 21314857 is about 4616.8015985095. The cubic root of 21314857 is about 277.2644192766.

The spelling of 21314857 in words is "twenty-one million, three hundred fourteen thousand, eight hundred fifty-seven".