21971075739 has 16 divisors (see below), whose sum is σ = 29408292864. Its totient is φ = 14590719200.

The previous prime is 21971075717. The next prime is 21971075743. The reversal of 21971075739 is 93757017912.

It is a cyclic number.

It is not a de Polignac number, because 21971075739 - 2¹⁶ = 21971010203 is a prime.

It is a super-2 number, since 2×21971075739² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21971075691 and 21971075700.

It is not an unprimeable number, because it can be changed into a prime (21971073739) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 931684 + ... + 954974.

It is an arithmetic number, because the mean of its divisors is an integer number (1838018304).

Almost surely, 2^21971075739 is an apocalyptic number.

21971075739 is a deficient number, since it is larger than the sum of its proper divisors (7437217125).

21971075739 is a wasteful number, since it uses less digits than its factorization.

21971075739 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24498.

The product of its (nonzero) digits is 833490, while the sum is 51.

The spelling of 21971075739 in words is "twenty-one billion, nine hundred seventy-one million, seventy-five thousand, seven hundred thirty-nine".