10399999999921 has 32 divisors (see below), whose sum is σ = 12160512000000. Its totient is φ = 8708886830592.

The previous prime is 10399999999919. The next prime is 10399999999927. The reversal of 10399999999921 is 12999999999301.

It is a cyclic number.

It is not a de Polignac number, because 10399999999921 - 2¹ = 10399999999919 is a prime.

It is not an unprimeable number, because it can be changed into a prime (10399999999927) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 426934740 + ... + 426959098.

It is an arithmetic number, because the mean of its divisors is an integer number (380016000000).

Almost surely, 2^{10399999999921} is an apocalyptic number.

It is an amenable number.

10399999999921 is a deficient number, since it is larger than the sum of its proper divisors (1760512000079).

10399999999921 is a wasteful number, since it uses less digits than its factorization.

10399999999921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26701.

The product of its (nonzero) digits is 2324522934, while the sum is 88.

The spelling of 10399999999921 in words is "ten trillion, three hundred ninety-nine billion, nine hundred ninety-nine million, nine hundred ninety-nine thousand, nine hundred twenty-one".