21235737145 has 16 divisors (see below), whose sum is σ = 29129084928. Its totient is φ = 14558754240.

The previous prime is 21235737109. The next prime is 21235737161. The reversal of 21235737145 is 54173753212.

It is a happy number.

It is not a de Polignac number, because 21235737145 - 2¹³ = 21235728953 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21235737098 and 21235737107.

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, 126472 + ... + 241798.

It is an arithmetic number, because the mean of its divisors is an integer number (1820567808).

Almost surely, 2^21235737145 is an apocalyptic number.

It is an amenable number.

21235737145 is a deficient number, since it is larger than the sum of its proper divisors (7893347783).

21235737145 is a wasteful number, since it uses less digits than its factorization.

21235737145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 120600.

The product of its digits is 176400, while the sum is 40.

The spelling of 21235737145 in words is "twenty-one billion, two hundred thirty-five million, seven hundred thirty-seven thousand, one hundred forty-five".