20400434261642 has 4 divisors (see below), whose sum is σ = 30600651392466. Its totient is φ = 10200217130820.

The previous prime is 20400434261561. The next prime is 20400434261653. The reversal of 20400434261642 is 24616243400402.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 17932421539561 + 2468012722081 = 4234669^2 + 1570991^2 .

It is a junction number, because it is equal to n+sod(n) for n = 20400434261596 and 20400434261605.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5100108565409 + ... + 5100108565412.

Almost surely, 2^{20400434261642} is an apocalyptic number.

20400434261642 is a deficient number, since it is larger than the sum of its proper divisors (10200217130824).

20400434261642 is a wasteful number, since it uses less digits than its factorization.

20400434261642 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10200217130823.

The product of its (nonzero) digits is 221184, while the sum is 38.

The spelling of 20400434261642 in words is "twenty trillion, four hundred billion, four hundred thirty-four million, two hundred sixty-one thousand, six hundred forty-two".