21399593795 has 32 divisors (see below), whose sum is σ = 27363764736. Its totient is φ = 16010035200.

The previous prime is 21399593791. The next prime is 21399593797. The reversal of 21399593795 is 59739599312.

It is a happy number.

It is a Cunningham number, because it is equal to 146286²-1.

It is not a de Polignac number, because 21399593795 - 2² = 21399593791 is a prime.

It is a super-2 number, since 2×21399593795² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21399593791) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 12433535 + ... + 12435255.

It is an arithmetic number, because the mean of its divisors is an integer number (855117648).

Almost surely, 2^21399593795 is an apocalyptic number.

21399593795 is a deficient number, since it is larger than the sum of its proper divisors (5964170941).

21399593795 is a wasteful number, since it uses less digits than its factorization.

21399593795 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2591.

The product of its digits is 20667150, while the sum is 62.

The spelling of 21399593795 in words is "twenty-one billion, three hundred ninety-nine million, five hundred ninety-three thousand, seven hundred ninety-five".