6900400646 has 4 divisors (see below), whose sum is σ = 10350600972. Its totient is φ = 3450200322.

The previous prime is 6900400609. The next prime is 6900400649. The reversal of 6900400646 is 6460040096.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6900400649) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1725100160 + ... + 1725100163.

It is an arithmetic number, because the mean of its divisors is an integer number (2587650243).

Almost surely, 2^6900400646 is an apocalyptic number.

6900400646 is a deficient number, since it is larger than the sum of its proper divisors (3450200326).

6900400646 is a wasteful number, since it uses less digits than its factorization.

6900400646 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3450200325.

The product of its (nonzero) digits is 31104, while the sum is 35.

The square root of 6900400646 is about 83068.6501996993. The cubic root of 6900400646 is about 1903.8151086485.

The spelling of 6900400646 in words is "six billion, nine hundred million, four hundred thousand, six hundred forty-six".