21100431995 has 16 divisors (see below), whose sum is σ = 25482753792. Its totient is φ = 16772311680.

The previous prime is 21100431973. The next prime is 21100432021. The reversal of 21100431995 is 59913400112.

It is a happy number.

It is not a de Polignac number, because 21100431995 - 2¹⁸ = 21100169851 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1570205 + ... + 1583585.

It is an arithmetic number, because the mean of its divisors is an integer number (1592672112).

Almost surely, 2^21100431995 is an apocalyptic number.

21100431995 is a deficient number, since it is larger than the sum of its proper divisors (4382321797).

21100431995 is a wasteful number, since it uses less digits than its factorization.

21100431995 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15382.

The product of its (nonzero) digits is 9720, while the sum is 35.

The spelling of 21100431995 in words is "twenty-one billion, one hundred million, four hundred thirty-one thousand, nine hundred ninety-five".