21245740776 has 96 divisors (see below), whose sum is σ = 64261884960. Its totient is φ = 6537143232.

The previous prime is 21245740753. The next prime is 21245740801. The reversal of 21245740776 is 67704754212.

21245740776 is a `hidden beast` number, since 2 + 1 + 2 + 4 + 574 + 0 + 7 + 76 = 666.

It is a super-2 number, since 2×21245740776² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 395070 + ... + 445613.

It is an arithmetic number, because the mean of its divisors is an integer number (669394635).

Almost surely, 2^21245740776 is an apocalyptic number.

21245740776 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

21245740776 is an abundant number, since it is smaller than the sum of its proper divisors (43016144184).

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

21245740776 is a wasteful number, since it uses less digits than its factorization.

21245740776 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 840717 (or 840701 counting only the distinct ones).

The product of its (nonzero) digits is 658560, while the sum is 45.

The spelling of 21245740776 in words is "twenty-one billion, two hundred forty-five million, seven hundred forty thousand, seven hundred seventy-six".