20340749641 has 9 divisors (see below), whose sum is σ = 20520447021. Its totient is φ = 20162616012.

The previous prime is 20340749633. The next prime is 20340749651. The reversal of 20340749641 is 14694704302.

The square root of 20340749641 is 142621.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 20340749641 - 2³ = 20340749633 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20340749594 and 20340749603.

It is not an unprimeable number, because it can be changed into a prime (20340749651) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 18112306 + ... + 18113428.

It is an arithmetic number, because the mean of its divisors is an integer number (2280049669).

Almost surely, 2^20340749641 is an apocalyptic number.

20340749641 is the 142621-st square number.

20340749641 is the 71311-st centered octagonal number.

It is an amenable number.

20340749641 is a deficient number, since it is larger than the sum of its proper divisors (179697380).

20340749641 is an frugal number, since it uses more digits than its factorization.

20340749641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2500 (or 1250 counting only the distinct ones).

The product of its (nonzero) digits is 145152, while the sum is 40.

The spelling of 20340749641 in words is "twenty billion, three hundred forty million, seven hundred forty-nine thousand, six hundred forty-one".