21419737 has 2 divisors, whose sum is σ = 21419738. Its totient is φ = 21419736.

The previous prime is 21419731. The next prime is 21419747. The reversal of 21419737 is 73791412.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20602521 + 817216 = 4539^2 + 904^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21419737 is a prime.

It is not a weakly prime, because it can be changed into another prime (21419731) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10709868 + 10709869.

It is an arithmetic number, because the mean of its divisors is an integer number (10709869).

Almost surely, 2^21419737 is an apocalyptic number.

It is an amenable number.

21419737 is a deficient number, since it is larger than the sum of its proper divisors (1).

21419737 is an equidigital number, since it uses as much as digits as its factorization.

21419737 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10584, while the sum is 34.

The square root of 21419737 is about 4628.1461731454. The cubic root of 21419737 is about 277.7184363490.

The spelling of 21419737 in words is "twenty-one million, four hundred nineteen thousand, seven hundred thirty-seven".