1904406779661 has 16 divisors (see below), whose sum is σ = 2557552972800. Its totient is φ = 1260433098288.

The previous prime is 1904406779659. The next prime is 1904406779663. The reversal of 1904406779661 is 1669776044091.

It is an interprime number because it is at equal distance from previous prime (1904406779659) and next prime (1904406779663).

It is not a de Polignac number, because 1904406779661 - 2¹ = 1904406779659 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1904406779595 and 1904406779604.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1904406779663) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 24934750 + ... + 25011008.

It is an arithmetic number, because the mean of its divisors is an integer number (159847060800).

Almost surely, 2^{1904406779661} is an apocalyptic number.

It is an amenable number.

1904406779661 is a deficient number, since it is larger than the sum of its proper divisors (653146193139).

1904406779661 is a wasteful number, since it uses less digits than its factorization.

1904406779661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 136288.

The product of its (nonzero) digits is 13716864, while the sum is 60.

The spelling of 1904406779661 in words is "one trillion, nine hundred four billion, four hundred six million, seven hundred seventy-nine thousand, six hundred sixty-one".