20297211636 has 36 divisors (see below), whose sum is σ = 51283492512. Its totient is φ = 6245295264.

The previous prime is 20297211617. The next prime is 20297211637. The reversal of 20297211636 is 63611279202.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a junction number, because it is equal to n+sod(n) for n = 20297211594 and 20297211603.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20297211637) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5002216 + ... + 5006271.

Almost surely, 2^20297211636 is an apocalyptic number.

20297211636 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

20297211636 is an abundant number, since it is smaller than the sum of its proper divisors (30986280876).

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

20297211636 is a wasteful number, since it uses less digits than its factorization.

20297211636 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10008520 (or 10008505 counting only the distinct ones).

The product of its (nonzero) digits is 54432, while the sum is 39.

The spelling of 20297211636 in words is "twenty billion, two hundred ninety-seven million, two hundred eleven thousand, six hundred thirty-six".