20402041521 has 16 divisors (see below), whose sum is σ = 28637706240. Its totient is φ = 12884032080.

The previous prime is 20402041481. The next prime is 20402041523. The reversal of 20402041521 is 12514020402.

It is not a de Polignac number, because 20402041521 - 2⁷ = 20402041393 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20402041523) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 715096 + ... + 743078.

It is an arithmetic number, because the mean of its divisors is an integer number (1789856640).

Almost surely, 2^20402041521 is an apocalyptic number.

It is an amenable number.

20402041521 is a deficient number, since it is larger than the sum of its proper divisors (8235664719).

20402041521 is a wasteful number, since it uses less digits than its factorization.

20402041521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40796.

The product of its (nonzero) digits is 640, while the sum is 21.

Adding to 20402041521 its reverse (12514020402), we get a palindrome (32916061923).

The spelling of 20402041521 in words is "twenty billion, four hundred two million, forty-one thousand, five hundred twenty-one".