20533253787 has 16 divisors (see below), whose sum is σ = 30504384000. Its totient is φ = 13650698952.

The previous prime is 20533253729. The next prime is 20533253791. The reversal of 20533253787 is 78735233502.

20533253787 is a `hidden beast` number, since 2 + 0 + 5 + 3 + 32 + 537 + 87 = 666.

It is not a de Polignac number, because 20533253787 - 2⁶ = 20533253723 is a prime.

It is a super-2 number, since 2×20533253787² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20533253087) 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, 1049487 + ... + 1068872.

It is an arithmetic number, because the mean of its divisors is an integer number (1906524000).

Almost surely, 2^20533253787 is an apocalyptic number.

20533253787 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

20533253787 is a deficient number, since it is larger than the sum of its proper divisors (9971130213).

20533253787 is a wasteful number, since it uses less digits than its factorization.

20533253787 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2118727 (or 2118721 counting only the distinct ones).

The product of its (nonzero) digits is 1058400, while the sum is 45.

The spelling of 20533253787 in words is "twenty billion, five hundred thirty-three million, two hundred fifty-three thousand, seven hundred eighty-seven".