661329070 has 16 divisors (see below), whose sum is σ = 1260415728. Its totient is φ = 248970880.

The previous prime is 661329049. The next prime is 661329091. The reversal of 661329070 is 70923166.

661329070 = 3085² + 3086² + ... + 3152².

It is an interprime number because it is at equal distance from previous prime (661329049) and next prime (661329091).

It is a super-2 number, since 2×661329070² = 874712277654129800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (34).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1944916 + ... + 1945255.

It is an arithmetic number, because the mean of its divisors is an integer number (78775983).

Almost surely, 2^661329070 is an apocalyptic number.

661329070 is a deficient number, since it is larger than the sum of its proper divisors (599086658).

661329070 is a wasteful number, since it uses less digits than its factorization.

661329070 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3890195.

The product of its (nonzero) digits is 13608, while the sum is 34.

The square root of 661329070 is about 25716.3191378549. The cubic root of 661329070 is about 871.2428047603.

The spelling of 661329070 in words is "six hundred sixty-one million, three hundred twenty-nine thousand, seventy".