21785548434 has 32 divisors (see below), whose sum is σ = 48962841984. Its totient is φ = 6411799680.

The previous prime is 21785548381. The next prime is 21785548469. The reversal of 21785548434 is 43484558712.

It is a super-2 number, since 2×21785548434² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6069987 + ... + 6073574.

It is an arithmetic number, because the mean of its divisors is an integer number (1530088812).

Almost surely, 2^21785548434 is an apocalyptic number.

21785548434 is an abundant number, since it is smaller than the sum of its proper divisors (27177293550).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21785548434 is a wasteful number, since it uses less digits than its factorization.

21785548434 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12143602.

The product of its digits is 4300800, while the sum is 51.

The spelling of 21785548434 in words is "twenty-one billion, seven hundred eighty-five million, five hundred forty-eight thousand, four hundred thirty-four".