780808969021 has 4 divisors (see below), whose sum is σ = 780810872544. Its totient is φ = 780807065500.

The previous prime is 780808968991. The next prime is 780808969027. The reversal of 780808969021 is 120969808087.

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, and also an emirpimes, since its reverse is a distinct semiprime: 120969808087 = 65119 ⋅1857673.

It is a cyclic number.

It is not a de Polignac number, because 780808969021 - 2²¹ = 780806871869 is a prime.

It is a super-2 number, since 2×780808969021² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (780808969027) 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, 54535 + ... + 1250836.

It is an arithmetic number, because the mean of its divisors is an integer number (195202718136).

Almost surely, 2^780808969021 is an apocalyptic number.

It is an amenable number.

780808969021 is a deficient number, since it is larger than the sum of its proper divisors (1903523).

780808969021 is a wasteful number, since it uses less digits than its factorization.

780808969021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1903522.

The product of its (nonzero) digits is 3483648, while the sum is 58.

The spelling of 780808969021 in words is "seven hundred eighty billion, eight hundred eight million, nine hundred sixty-nine thousand, twenty-one".