21436742472 has 16 divisors (see below), whose sum is σ = 53591856240. Its totient is φ = 7145580816.

The previous prime is 21436742471. The next prime is 21436742473. The reversal of 21436742472 is 27424763412.

It is an interprime number because it is at equal distance from previous prime (21436742471) and next prime (21436742473).

It is not an unprimeable number, because it can be changed into a prime (21436742471) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 446598778 + ... + 446598825.

It is an arithmetic number, because the mean of its divisors is an integer number (3349491015).

Almost surely, 2^21436742472 is an apocalyptic number.

It is an amenable number.

21436742472 is an abundant number, since it is smaller than the sum of its proper divisors (32155113768).

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

21436742472 is a wasteful number, since it uses less digits than its factorization.

21436742472 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 893197612 (or 893197608 counting only the distinct ones).

The product of its digits is 451584, while the sum is 42.

The spelling of 21436742472 in words is "twenty-one billion, four hundred thirty-six million, seven hundred forty-two thousand, four hundred seventy-two".