21403301240 has 32 divisors (see below), whose sum is σ = 50990219280. Its totient is φ = 8057713152.

The previous prime is 21403301221. The next prime is 21403301261. The reversal of 21403301240 is 4210330412.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15737042 + ... + 15738401.

Almost surely, 2^21403301240 is an apocalyptic number.

21403301240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21403301240 is an abundant number, since it is smaller than the sum of its proper divisors (29586918040).

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

21403301240 is a wasteful number, since it uses less digits than its factorization.

21403301240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31475471 (or 31475467 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 20.

Adding to 21403301240 its reverse (4210330412), we get a palindrome (25613631652).

The spelling of 21403301240 in words is "twenty-one billion, four hundred three million, three hundred one thousand, two hundred forty".