21123300451544 has 8 divisors (see below), whose sum is σ = 39606188346660. Its totient is φ = 10561650225768.

The previous prime is 21123300451537. The next prime is 21123300451553. The reversal of 21123300451544 is 44515400332112.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1320206278214 + ... + 1320206278229.

Almost surely, 2^{21123300451544} is an apocalyptic number.

It is an amenable number.

21123300451544 is a deficient number, since it is larger than the sum of its proper divisors (18482887895116).

21123300451544 is a wasteful number, since it uses less digits than its factorization.

21123300451544 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2640412556449 (or 2640412556445 counting only the distinct ones).

The product of its (nonzero) digits is 57600, while the sum is 35.

Adding to 21123300451544 its reverse (44515400332112), we get a palindrome (65638700783656).

The spelling of 21123300451544 in words is "twenty-one trillion, one hundred twenty-three billion, three hundred million, four hundred fifty-one thousand, five hundred forty-four".