70139695921 has 3 divisors (see below), whose sum is σ = 70139960761. Its totient is φ = 70139431082.

The previous prime is 70139695897. The next prime is 70139695943. The reversal of 70139695921 is 12959693107.

It is a happy number.

The square root of 70139695921 is 264839.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 12959693107 = 1913 ⋅6774539.

It is not a de Polignac number, because 70139695921 - 2⁵ = 70139695889 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (70139695421) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 132420 + ... + 397258.

Almost surely, 2^70139695921 is an apocalyptic number.

70139695921 is the 264839-th square number.

70139695921 is the 132420-th centered octagonal number.

It is an amenable number.

70139695921 is a deficient number, since it is larger than the sum of its proper divisors (264840).

70139695921 is an frugal number, since it uses more digits than its factorization.

70139695921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 529678 (or 264839 counting only the distinct ones).

The product of its (nonzero) digits is 918540, while the sum is 52.

The spelling of 70139695921 in words is "seventy billion, one hundred thirty-nine million, six hundred ninety-five thousand, nine hundred twenty-one".