21531201354 has 64 divisors (see below), whose sum is σ = 52372481280. Its totient is φ = 6516365760.

The previous prime is 21531201353. The next prime is 21531201361. The reversal of 21531201354 is 45310213512.

21531201354 is a `hidden beast` number, since 215 + 312 + 0 + 135 + 4 = 666.

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

It is not an unprimeable number, because it can be changed into a prime (21531201353) 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, 208582 + ... + 294225.

It is an arithmetic number, because the mean of its divisors is an integer number (818320020).

Almost surely, 2^21531201354 is an apocalyptic number.

21531201354 is an abundant number, since it is smaller than the sum of its proper divisors (30841279926).

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

21531201354 is a wasteful number, since it uses less digits than its factorization.

21531201354 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 502892 (or 502886 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 27.

Adding to 21531201354 its reverse (45310213512), we get a palindrome (66841414866).

The spelling of 21531201354 in words is "twenty-one billion, five hundred thirty-one million, two hundred one thousand, three hundred fifty-four".