21375866793 has 24 divisors (see below), whose sum is σ = 30789545760. Its totient is φ = 13184949760.

The previous prime is 21375866791. The next prime is 21375866807. The reversal of 21375866793 is 39766857312.

It is not a de Polignac number, because 21375866793 - 2¹ = 21375866791 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21375866791) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 157788 + ... + 260093.

It is an arithmetic number, because the mean of its divisors is an integer number (1282897740).

Almost surely, 2^21375866793 is an apocalyptic number.

It is an amenable number.

21375866793 is a deficient number, since it is larger than the sum of its proper divisors (9413678967).

21375866793 is a wasteful number, since it uses less digits than its factorization.

21375866793 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 417977 (or 417960 counting only the distinct ones).

The product of its digits is 11430720, while the sum is 57.

The spelling of 21375866793 in words is "twenty-one billion, three hundred seventy-five million, eight hundred sixty-six thousand, seven hundred ninety-three".