1377660421 has 2 divisors, whose sum is σ = 1377660422. Its totient is φ = 1377660420.

The previous prime is 1377660419. The next prime is 1377660439. The reversal of 1377660421 is 1240667731.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1338535396 + 39125025 = 36586^2 + 6255^2 .

It is an emirp because it is prime and its reverse (1240667731) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1377660421 - 2¹ = 1377660419 is a prime.

Together with 1377660419, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1377660451) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 688830210 + 688830211.

It is an arithmetic number, because the mean of its divisors is an integer number (688830211).

Almost surely, 2^1377660421 is an apocalyptic number.

It is an amenable number.

1377660421 is a deficient number, since it is larger than the sum of its proper divisors (1).

1377660421 is an equidigital number, since it uses as much as digits as its factorization.

1377660421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 42336, while the sum is 37.

The square root of 1377660421 is about 37116.8482094048. The cubic root of 1377660421 is about 1112.7067618227.

The spelling of 1377660421 in words is "one billion, three hundred seventy-seven million, six hundred sixty thousand, four hundred twenty-one".