21649150474656 has 48 divisors (see below), whose sum is σ = 56866139271648. Its totient is φ = 7211669932800.

The previous prime is 21649150474639. The next prime is 21649150474657. The reversal of 21649150474656 is 65647405194612.

It is a tau number, because it is divible by the number of its divisors (48).

It is a super-2 number, since 2×21649150474656² (a number of 27 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21649150474656.

It is not an unprimeable number, because it can be changed into a prime (21649150474657) 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, 73501615 + ... + 73795566.

It is an arithmetic number, because the mean of its divisors is an integer number (1184711234826).

Almost surely, 2^{21649150474656} is an apocalyptic number.

It is an amenable number.

21649150474656 is an abundant number, since it is smaller than the sum of its proper divisors (35216988796992).

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

21649150474656 is a wasteful number, since it uses less digits than its factorization.

21649150474656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 147298725 (or 147298717 counting only the distinct ones).

The product of its (nonzero) digits is 43545600, while the sum is 60.

The spelling of 21649150474656 in words is "twenty-one trillion, six hundred forty-nine billion, one hundred fifty million, four hundred seventy-four thousand, six hundred fifty-six".