20421644661354 has 16 divisors (see below), whose sum is σ = 40948284929760. Its totient is φ = 6789715619280.

The previous prime is 20421644661323. The next prime is 20421644661373. The reversal of 20421644661354 is 45316644612402.

It is a super-2 number, since 2×20421644661354² (a number of 27 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4374814432 + ... + 4374819099.

It is an arithmetic number, because the mean of its divisors is an integer number (2559267808110).

Almost surely, 2^{20421644661354} is an apocalyptic number.

20421644661354 is an abundant number, since it is smaller than the sum of its proper divisors (20526640268406).

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

20421644661354 is a wasteful number, since it uses less digits than its factorization.

20421644661354 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8749633925.

The product of its (nonzero) digits is 3317760, while the sum is 48.

The spelling of 20421644661354 in words is "twenty trillion, four hundred twenty-one billion, six hundred forty-four million, six hundred sixty-one thousand, three hundred fifty-four".