21147402452 has 24 divisors (see below), whose sum is σ = 40382919360. Its totient is φ = 9609930560.

The previous prime is 21147402449. The next prime is 21147402457. The reversal of 21147402452 is 25420474112.

It is a super-2 number, since 2×21147402452² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21147402457) 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, 111713 + ... + 234039.

It is an arithmetic number, because the mean of its divisors is an integer number (1682621640).

Almost surely, 2^21147402452 is an apocalyptic number.

21147402452 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21147402452 is a deficient number, since it is larger than the sum of its proper divisors (19235516908).

21147402452 is a wasteful number, since it uses less digits than its factorization.

21147402452 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 126271 (or 126269 counting only the distinct ones).

The product of its (nonzero) digits is 17920, while the sum is 32.

Adding to 21147402452 its reverse (25420474112), we get a palindrome (46567876564).

The spelling of 21147402452 in words is "twenty-one billion, one hundred forty-seven million, four hundred two thousand, four hundred fifty-two".