21851641703 has 2 divisors, whose sum is σ = 21851641704. Its totient is φ = 21851641702.

The previous prime is 21851641697. The next prime is 21851641741. The reversal of 21851641703 is 30714615812.

It is an a-pointer prime, because the next prime (21851641741) can be obtained adding 21851641703 to its sum of digits (38).

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21851641703 - 2²⁴ = 21834864487 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21851640703) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10925820851 + 10925820852.

It is an arithmetic number, because the mean of its divisors is an integer number (10925820852).

Almost surely, 2^21851641703 is an apocalyptic number.

21851641703 is a deficient number, since it is larger than the sum of its proper divisors (1).

21851641703 is an equidigital number, since it uses as much as digits as its factorization.

21851641703 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 40320, while the sum is 38.

The spelling of 21851641703 in words is "twenty-one billion, eight hundred fifty-one million, six hundred forty-one thousand, seven hundred three".