70921957 has 4 divisors (see below), whose sum is σ = 70944940. Its totient is φ = 70898976.

The previous prime is 70921931. The next prime is 70921969. The reversal of 70921957 is 75912907.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 6937956 + 63984001 = 2634^2 + 7999^2 .

It is a cyclic number.

It is not a de Polignac number, because 70921957 - 2¹⁹ = 70397669 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (70921057) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5982 + ... + 13327.

It is an arithmetic number, because the mean of its divisors is an integer number (17736235).

Almost surely, 2^70921957 is an apocalyptic number.

It is an amenable number.

70921957 is a deficient number, since it is larger than the sum of its proper divisors (22983).

70921957 is a wasteful number, since it uses less digits than its factorization.

70921957 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22982.

The product of its (nonzero) digits is 39690, while the sum is 40.

The square root of 70921957 is about 8421.5174998334. The cubic root of 70921957 is about 413.9300001450.

The spelling of 70921957 in words is "seventy million, nine hundred twenty-one thousand, nine hundred fifty-seven".