21142120240 has 40 divisors (see below), whose sum is σ = 49359439008. Its totient is φ = 8421749760.

The previous prime is 21142120189. The next prime is 21142120243. The reversal of 21142120240 is 4202124112.

It is a tau number, because it is divible by the number of its divisors (40).

It is not an unprimeable number, because it can be changed into a prime (21142120243) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 529012 + ... + 567571.

Almost surely, 2^21142120240 is an apocalyptic number.

21142120240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21142120240 is an abundant number, since it is smaller than the sum of its proper divisors (28217318768).

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

21142120240 is a wasteful number, since it uses less digits than its factorization.

21142120240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1096837 (or 1096831 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 19.

Adding to 21142120240 its reverse (4202124112), we get a palindrome (25344244352).

The spelling of 21142120240 in words is "twenty-one billion, one hundred forty-two million, one hundred twenty thousand, two hundred forty".