21173346782 has 32 divisors (see below), whose sum is σ = 37329715200. Its totient is φ = 9002803320.

The previous prime is 21173346773. The next prime is 21173346791. The reversal of 21173346782 is 28764337112.

It is an interprime number because it is at equal distance from previous prime (21173346773) and next prime (21173346791).

It is a super-2 number, since 2×21173346782² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 34394 + ... + 208637.

It is an arithmetic number, because the mean of its divisors is an integer number (1166553600).

Almost surely, 2^21173346782 is an apocalyptic number.

21173346782 is a deficient number, since it is larger than the sum of its proper divisors (16156368418).

21173346782 is a wasteful number, since it uses less digits than its factorization.

21173346782 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 243181 (or 243167 counting only the distinct ones).

The product of its digits is 338688, while the sum is 44.

The spelling of 21173346782 in words is "twenty-one billion, one hundred seventy-three million, three hundred forty-six thousand, seven hundred eighty-two".