20696400840 has 32 divisors (see below), whose sum is σ = 62089202880. Its totient is φ = 5519040192.

The previous prime is 20696400839. The next prime is 20696400863. The reversal of 20696400840 is 4800469602.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 86234884 + ... + 86235123.

It is an arithmetic number, because the mean of its divisors is an integer number (1940287590).

Almost surely, 2^20696400840 is an apocalyptic number.

20696400840 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20696400840 is an abundant number, since it is smaller than the sum of its proper divisors (41392802040).

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

20696400840 is a wasteful number, since it uses less digits than its factorization.

20696400840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 172470021 (or 172470017 counting only the distinct ones).

The product of its (nonzero) digits is 82944, while the sum is 39.

The spelling of 20696400840 in words is "twenty billion, six hundred ninety-six million, four hundred thousand, eight hundred forty".