20720489156 has 24 divisors (see below), whose sum is σ = 37620608256. Its totient is φ = 9975137760.

The previous prime is 20720489143. The next prime is 20720489161. The reversal of 20720489156 is 65198402702.

It is a happy number.

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, 399686 + ... + 448541.

It is an arithmetic number, because the mean of its divisors is an integer number (1567525344).

Almost surely, 2^20720489156 is an apocalyptic number.

It is an amenable number.

20720489156 is a deficient number, since it is larger than the sum of its proper divisors (16900119100).

20720489156 is a wasteful number, since it uses less digits than its factorization.

20720489156 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 848459 (or 848457 counting only the distinct ones).

The product of its (nonzero) digits is 241920, while the sum is 44.

The spelling of 20720489156 in words is "twenty billion, seven hundred twenty million, four hundred eighty-nine thousand, one hundred fifty-six".