21245164143540 has 48 divisors (see below), whose sum is σ = 59486669911872. Its totient is φ = 5665357075456.

The previous prime is 21245164143523. The next prime is 21245164143557. The reversal of 21245164143540 is 4534146154212.

It is an interprime number because it is at equal distance from previous prime (21245164143523) and next prime (21245164143557).

It is a junction number, because it is equal to n+sod(n) for n = 21245164143492 and 21245164143501.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 25496587 + ... + 26316653.

It is an arithmetic number, because the mean of its divisors is an integer number (1239305623164).

Almost surely, 2^{21245164143540} is an apocalyptic number.

21245164143540 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21245164143540 is an abundant number, since it is smaller than the sum of its proper divisors (38241505768332).

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

21245164143540 is a wasteful number, since it uses less digits than its factorization.

21245164143540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1251856 (or 1251854 counting only the distinct ones).

The product of its (nonzero) digits is 460800, while the sum is 42.

The spelling of 21245164143540 in words is "twenty-one trillion, two hundred forty-five billion, one hundred sixty-four million, one hundred forty-three thousand, five hundred forty".