20640000154 has 16 divisors (see below), whose sum is σ = 31838847048. Its totient is φ = 10027789632.

The previous prime is 20640000131. The next prime is 20640000209. The reversal of 20640000154 is 45100004602.

It can be written as a sum of positive squares in 4 ways, for example, as 19022753929 + 1617246225 = 137923^2 + 40215^2 .

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, 128209 + ... + 240244.

Almost surely, 2^20640000154 is an apocalyptic number.

20640000154 is a deficient number, since it is larger than the sum of its proper divisors (11198846894).

20640000154 is a wasteful number, since it uses less digits than its factorization.

20640000154 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 369249.

The product of its (nonzero) digits is 960, while the sum is 22.

Adding to 20640000154 its reverse (45100004602), we get a palindrome (65740004756).

The spelling of 20640000154 in words is "twenty billion, six hundred forty million, one hundred fifty-four", and thus it is an aban number.