7759778401421 has 4 divisors (see below), whose sum is σ = 8097160071072. Its totient is φ = 7422396731772.

The previous prime is 7759778401387. The next prime is 7759778401447. The reversal of 7759778401421 is 1241048779577.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 7759778401421 - 2¹⁸ = 7759778139277 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7759778400421) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 168690834791 + ... + 168690834836.

It is an arithmetic number, because the mean of its divisors is an integer number (2024290017768).

Almost surely, 2^{7759778401421} is an apocalyptic number.

It is an amenable number.

7759778401421 is a deficient number, since it is larger than the sum of its proper divisors (337381669651).

7759778401421 is a wasteful number, since it uses less digits than its factorization.

7759778401421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 337381669650.

The product of its (nonzero) digits is 27659520, while the sum is 62.

The spelling of 7759778401421 in words is "seven trillion, seven hundred fifty-nine billion, seven hundred seventy-eight million, four hundred one thousand, four hundred twenty-one".