1421917857 has 6 divisors (see below), whose sum is σ = 2053881362. Its totient is φ = 947945232.

The previous prime is 1421917853. The next prime is 1421917873. The reversal of 1421917857 is 7587191241.

It is a happy number.

1421917857 is a `hidden beast` number, since 1 + 421 + 9 + 178 + 57 = 666.

It can be written as a sum of positive squares in only one way, i.e., 1099320336 + 322597521 = 33156^2 + 17961^2 .

It is not a de Polignac number, because 1421917857 - 2² = 1421917853 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1421917853) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 78995428 + ... + 78995445.

Almost surely, 2^1421917857 is an apocalyptic number.

It is an amenable number.

1421917857 is a deficient number, since it is larger than the sum of its proper divisors (631963505).

1421917857 is a wasteful number, since it uses less digits than its factorization.

1421917857 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 157990879 (or 157990876 counting only the distinct ones).

The product of its digits is 141120, while the sum is 45.

The square root of 1421917857 is about 37708.3260965002. The cubic root of 1421917857 is about 1124.4966589798.

The spelling of 1421917857 in words is "one billion, four hundred twenty-one million, nine hundred seventeen thousand, eight hundred fifty-seven".