21142155040 has 24 divisors (see below), whose sum is σ = 49948341660. Its totient is φ = 8456861952.

The previous prime is 21142154977. The next prime is 21142155071. The reversal of 21142155040 is 4055124112.

It can be written as a sum of positive squares in 2 ways, for example, as 19306546704 + 1835608336 = 138948^2 + 42844^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21142154996 and 21142155014.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 66069075 + ... + 66069394.

Almost surely, 2^21142155040 is an apocalyptic number.

21142155040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21142155040 is an abundant number, since it is smaller than the sum of its proper divisors (28806186620).

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

21142155040 is a wasteful number, since it uses less digits than its factorization.

21142155040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 132138484 (or 132138476 counting only the distinct ones).

The product of its (nonzero) digits is 1600, while the sum is 25.

Adding to 21142155040 its reverse (4055124112), we get a palindrome (25197279152).

The spelling of 21142155040 in words is "twenty-one billion, one hundred forty-two million, one hundred fifty-five thousand, forty".