1921280477 has 2 divisors, whose sum is σ = 1921280478. Its totient is φ = 1921280476.

The previous prime is 1921280467. The next prime is 1921280507. The reversal of 1921280477 is 7740821291.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1118634916 + 802645561 = 33446^2 + 28331^2 .

It is a cyclic number.

It is not a de Polignac number, because 1921280477 - 2²⁴ = 1904503261 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1921280407) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 960640238 + 960640239.

It is an arithmetic number, because the mean of its divisors is an integer number (960640239).

Almost surely, 2^1921280477 is an apocalyptic number.

It is an amenable number.

1921280477 is a deficient number, since it is larger than the sum of its proper divisors (1).

1921280477 is an equidigital number, since it uses as much as digits as its factorization.

1921280477 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 56448, while the sum is 41.

The square root of 1921280477 is about 43832.4135429479. The cubic root of 1921280477 is about 1243.1692423532.

The spelling of 1921280477 in words is "one billion, nine hundred twenty-one million, two hundred eighty thousand, four hundred seventy-seven".