21955743 has 6 divisors (see below), whose sum is σ = 31713864. Its totient is φ = 14637156.

The previous prime is 21955733. The next prime is 21955753. The reversal of 21955743 is 34755912.

It is an interprime number because it is at equal distance from previous prime (21955733) and next prime (21955753).

It is not a de Polignac number, because 21955743 - 2⁵ = 21955711 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21955698 and 21955707.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21955733) 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 5 ways as a sum of consecutive naturals, for example, 1219755 + ... + 1219772.

It is an arithmetic number, because the mean of its divisors is an integer number (5285644).

Almost surely, 2^21955743 is an apocalyptic number.

21955743 is a deficient number, since it is larger than the sum of its proper divisors (9758121).

21955743 is a wasteful number, since it uses less digits than its factorization.

21955743 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2439533 (or 2439530 counting only the distinct ones).

The product of its digits is 37800, while the sum is 36.

The square root of 21955743 is about 4685.6955726978. The cubic root of 21955743 is about 280.0159132112.

The spelling of 21955743 in words is "twenty-one million, nine hundred fifty-five thousand, seven hundred forty-three".