781421953 has 16 divisors (see below), whose sum is σ = 871589376. Its totient is φ = 695983680.

The previous prime is 781421939. The next prime is 781421959. The reversal of 781421953 is 359124187.

It is a cyclic number.

It is not a de Polignac number, because 781421953 - 2⁹ = 781421441 is a prime.

It is a super-2 number, since 2×781421953² = 1221240537260668418, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (781421959) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 34375 + ... + 52387.

It is an arithmetic number, because the mean of its divisors is an integer number (54474336).

Almost surely, 2^781421953 is an apocalyptic number.

It is an amenable number.

781421953 is a deficient number, since it is larger than the sum of its proper divisors (90167423).

781421953 is a wasteful number, since it uses less digits than its factorization.

781421953 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18144.

The product of its digits is 60480, while the sum is 40.

The square root of 781421953 is about 27953.9255382853. The cubic root of 781421953 is about 921.0754409318.

The spelling of 781421953 in words is "seven hundred eighty-one million, four hundred twenty-one thousand, nine hundred fifty-three".