21150205464265 has 32 divisors (see below), whose sum is σ = 25996318064640. Its totient is φ = 16510241555136.

The previous prime is 21150205464251. The next prime is 21150205464299. The reversal of 21150205464265 is 56246450205112.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 21150205464265 - 2⁹ = 21150205463753 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (43).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 981027556 + ... + 981049114.

It is an arithmetic number, because the mean of its divisors is an integer number (812384939520).

Almost surely, 2^{21150205464265} is an apocalyptic number.

It is an amenable number.

21150205464265 is a deficient number, since it is larger than the sum of its proper divisors (4846112600375).

21150205464265 is a wasteful number, since it uses less digits than its factorization.

21150205464265 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25933.

The product of its (nonzero) digits is 576000, while the sum is 43.

Adding to 21150205464265 its reverse (56246450205112), we get a palindrome (77396655669377).

The spelling of 21150205464265 in words is "twenty-one trillion, one hundred fifty billion, two hundred five million, four hundred sixty-four thousand, two hundred sixty-five".