781216051 has 12 divisors (see below), whose sum is σ = 981363376. Its totient is φ = 608739120.

The previous prime is 781216031. The next prime is 781216061. The reversal of 781216051 is 150612187.

It is not a de Polignac number, because 781216051 - 2⁵ = 781216019 is a prime.

It is a super-2 number, since 2×781216051² = 1220597036680069202, which contains 22 as substring.

It is a hoax number, since the sum of its digits (31) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (781216031) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 460320 + ... + 462013.

Almost surely, 2^781216051 is an apocalyptic number.

781216051 is a deficient number, since it is larger than the sum of its proper divisors (200147325).

781216051 is a wasteful number, since it uses less digits than its factorization.

781216051 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 922362 (or 922351 counting only the distinct ones).

The product of its (nonzero) digits is 3360, while the sum is 31.

The square root of 781216051 is about 27950.2424139756. The cubic root of 781216051 is about 920.9945337537.

The spelling of 781216051 in words is "seven hundred eighty-one million, two hundred sixteen thousand, fifty-one".