21000001210999 has 8 divisors (see below), whose sum is σ = 21913092345312. Its totient is φ = 20086914043680.

The previous prime is 21000001210973. The next prime is 21000001211003. The reversal of 21000001210999 is 99901210000012.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21000001210999 - 2⁴¹ = 18800977955447 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21000001210919) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16074457 + ... + 17331709.

It is an arithmetic number, because the mean of its divisors is an integer number (2739136543164).

Almost surely, 2^{21000001210999} is an apocalyptic number.

21000001210999 is a deficient number, since it is larger than the sum of its proper divisors (913091134313).

21000001210999 is a wasteful number, since it uses less digits than its factorization.

21000001210999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1983497.

The product of its (nonzero) digits is 2916, while the sum is 34.

The spelling of 21000001210999 in words is "twenty-one trillion, one million, two hundred ten thousand, nine hundred ninety-nine".