21253214511 has 32 divisors (see below), whose sum is σ = 32639604480. Its totient is φ = 13656960288.

The previous prime is 21253214447. The next prime is 21253214539. The reversal of 21253214511 is 11541235212.

It is a happy number.

21253214511 is a `hidden beast` number, since 2 + 125 + 3 + 21 + 4 + 511 = 666.

It is not a de Polignac number, because 21253214511 - 2⁶ = 21253214447 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21253214111) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 7480 + ... + 206306.

It is an arithmetic number, because the mean of its divisors is an integer number (1019987640).

Almost surely, 2^21253214511 is an apocalyptic number.

21253214511 is a deficient number, since it is larger than the sum of its proper divisors (11386389969).

21253214511 is a wasteful number, since it uses less digits than its factorization.

21253214511 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 198980 (or 198974 counting only the distinct ones).

The product of its digits is 2400, while the sum is 27.

Adding to 21253214511 its reverse (11541235212), we get a palindrome (32794449723).

The spelling of 21253214511 in words is "twenty-one billion, two hundred fifty-three million, two hundred fourteen thousand, five hundred eleven".