29961391690 has 36 divisors (see below), whose sum is σ = 54484912818. Its totient is φ = 11862602640.

The previous prime is 29961391661. The next prime is 29961391699. The reversal of 29961391690 is 9619316992.

It can be written as a sum of positive squares in only one way, i.e., 26965252521 + 2996139169 = 164211^2 + 54737^2 .

It is a super-2 number, since 2×29961391690² (a number of 22 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (29961391699) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 69515775 + ... + 69516205.

Almost surely, 2^29961391690 is an apocalyptic number.

29961391690 is a deficient number, since it is larger than the sum of its proper divisors (24523521128).

29961391690 is an frugal number, since it uses more digits than its factorization.

29961391690 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1123 (or 565 counting only the distinct ones).

The product of its (nonzero) digits is 1417176, while the sum is 55.

The spelling of 29961391690 in words is "twenty-nine billion, nine hundred sixty-one million, three hundred ninety-one thousand, six hundred ninety".